RBMC: Add rbmctool redundancy override options

[spinler]

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

[geissonator]

Does the the -d shows if the override is being used to enable/disable redundancy? If not can we add that (maybe under -e) so we know the value of the override?

[spinler]

Yep, it's built in already:

root@huygens:~# rbmctool -s
<6> Setting disable redundancy override to True
root@huygens:~# rbmctool -de

Local BMC
-----------------------------
Role:                Active
BMC Position:        0
Redundancy Enabled:  false
BMC State:           Ready
Failovers Allowed:   false
FW version hash:     7969307F
Provisioned:         true
Role Reason:         Sibling is already passive
Reasons for no BMC redundancy:
    Manually disabled    <---------------------------------