RBMC: Add rbmctool redundancy override options

Add options to set or clear the `DisableRedundancyOverride` D-Bus
property that manually disables redundancy:

```
-s,--set-disable-redundancy-override Excludes: --clear-disable-redundancy-override
                            Set override to disable redundancy

-c,--clear-disable-redundancy-override Excludes: --set-disable-redundancy-override
                            Clear override to disable redundancy
```

Also refactor the CLI11 argument handling to add option groups to make
it more explicit that only one argument can be handled at a time. This
changes the help text a bit. It now looks like:

```
$ ./rbmctool -h
RBMC Tool
[Exactly 1 of the following options is required]
Usage: ./rbmctool [OPTIONS]

Options:
  -h,--help                   Print this help message and exit
[Option Group: Display RBMC information]
  Options:
    -d                          Display basic RBMC information
    -e Needs: -d                Add in extended details
[Option Group: Modify the redundancy override]
  Options:
    -s,--set-disable-redundancy-override Excludes: --clear-disable-redundancy-override
                                Set override to disable redundancy
    -c,--clear-disable-redundancy-override Excludes: --set-disable-redundancy-override
                                Clear override to disable redundancy
[Option Group: Reset sibling BMC]
  Options:
    --reset-sibling             Reset the sibling BMC
```

Finally, it also does some small clean up to remove some unnecessary
co_return statements and also return nonzero if the sibling reset option
fails.

Testing:

When it works:
```
$ ./rbmctool -s
<6> Setting disable redundancy override to True

$ ./rbmctool -d | grep Enabled
Redundancy Enabled:  false

$ ./rbmctool -c
<6> Setting disable redundancy override to False

$ ./rbmctool -d | grep Enabled
Redundancy Enabled:  true

```

When it fails:
```
$ ./rbmctool -s
<6> Setting disable redundancy override to True
Error: Setting cannot be modified now (see journal for details)
```

Change-Id: I89b26bd6b744ee282ae643094adca4cf891098ae
Signed-off-by: Matt Spinler <spinler@us.ibm.com>

Author: spinler

redundant-bmc/src/rbmc_tool.cpp

@@ -148,8 +148,6 @@ sdbusplus::async::task<> displayLocalBMCInfo(sdbusplus::async::context& ctx,
         std::cout << "Cannot get to Redundancy interface on D-Bus: " << e.what()
                   << "\n";
     }
-
-    co_return;
 }
 
 // NOLINTBEGIN
@@ -222,7 +220,6 @@ sdbusplus::async::task<> displayInfo(sdbusplus::async::context& ctx,
     std::cout << "\n";
     co_await displaySiblingBMCInfo(ctx, extended);
     std::cout << "\n";
-    co_return;
 }
 
 void resetSiblingBMC()
@@ -236,7 +233,7 @@ void resetSiblingBMC()
     catch (const std::exception& e)
     {
         lg2::error("Failed asserting sibling reset: {ERROR}", "ERROR", e);
-        return;
+        exit(EXIT_FAILURE);
     }
 
     using namespace std::chrono_literals;
@@ -249,6 +246,43 @@ void resetSiblingBMC()
     catch (const std::exception& e)
     {
         lg2::error("Failed releasing sibling reset: {ERROR}", "ERROR", e);
+        exit(EXIT_FAILURE);
+    }
+}
+
+// NOLINTNEXTLINE
+sdbusplus::async::task<> modifyRedundancyOverride(
+    sdbusplus::async::context& ctx, bool disable)
+{
+    auto path =
+        sdbusplus::message::object_path{Redundancy::namespace_path::value} /
+        Redundancy::namespace_path::bmc;
+
+    try
+    {
+        // Use lg2 so it shows up in the journal as coming from rbmctool.
+        lg2::info("Setting disable redundancy override to {DISABLED}",
+                  "DISABLED", disable);
+
+        co_await Redundancy(ctx)
+            .service(Redundancy::interface)
+            .path(path.str)
+            .disable_redundancy_override(disable);
+    }
+    catch (const sdbusplus::exception_t& e)
+    {
+        if (std::string{"xyz.openbmc_project.Common.Error.Unavailable"} ==
+            e.name())
+        {
+            std::cout
+                << "Error: Setting cannot be modified now (see journal for details)\n";
+        }
+        else
+        {
+            std::cout << "Unexpected error: " << e.what() << '\n';
+        }
+
+        exit(EXIT_FAILURE);
     }
 }
 
@@ -258,13 +292,32 @@ int main(int argc, char** argv)
     bool info{};
     bool extended{};
     bool resetSibling{};
+    bool disableRedundancy{};
+    bool enableRedundancy{};
     sdbusplus::async::context ctx;
 
-    auto* flag = app.add_flag("-d", info, "Display RBMC Information");
-    app.add_flag("-e", extended, "Add extended RBMC details to the display")
+    auto* displayGroup = app.add_option_group("Display RBMC information");
+    auto* flag =
+        displayGroup->add_flag("-d", info, "Display basic RBMC information");
+    displayGroup->add_flag("-e", extended, "Add in extended details")
         ->needs(flag);
 
-    app.add_flag("--reset-sibling", resetSibling, "Reset the sibling BMC");
+    auto* overrideGroup =
+        app.add_option_group("Modify the redundancy override");
+    auto* disable = overrideGroup->add_flag(
+        "-s, --set-disable-redundancy-override", disableRedundancy,
+        "Set override to disable redundancy");
+
+    overrideGroup
+        ->add_flag("-c, --clear-disable-redundancy-override", enableRedundancy,
+                   "Clear override to disable redundancy")
+        ->excludes(disable);
+
+    auto* resetGroup = app.add_option_group("Reset sibling BMC");
+    resetGroup->add_flag("--reset-sibling", resetSibling,
+                         "Reset the sibling BMC");
+
+    app.require_option(1);
 
     CLI11_PARSE(app, argc, argv);
 
@@ -276,6 +329,14 @@ int main(int argc, char** argv)
     {
         resetSiblingBMC();
     }
+    else if (disableRedundancy)
+    {
+        ctx.spawn(modifyRedundancyOverride(ctx, true));
+    }
+    else if (enableRedundancy)
+    {
+        ctx.spawn(modifyRedundancyOverride(ctx, false));
+    }
     else
     {
         std::cout << app.help();