Fix invalid memory access when connecting to Online Lobby

[JAJames]

Fixes #91: Memory corruption on connecting to Online Lobby
This should remain a draft PR until this has been tested.

Analysis:

• bind_ptr->name.ids is currently being assigned to some stack memory, instead of the copy that's allocated via SnmpUtilMemAlloc. That's probably the main cause of the originally reported issue
• SnmpExtensionQuery is documented as potentially allocating/reallocating/freeing memory on the VarBindList. This is validated by the fact that the reported crash happens in that function, when it attempts to free the aforementioned stack memory. So for safety, we should probably assume it invalidates any pointers.
• SnmpUtilVarBindListFree handles cleaning up members of the SnmpVarBindList. Based on example usage and peeking at the ReactOS implementation, it seems like the actual SnmpVarBindList is not free'd by the function, because it's not necessarily expected to be allocated via SnmpUtilMemAlloc. So there's an opportunity to clean this up to not require calling SnmpUtilMemFree directly at all.
• The existing code doesn't free some of the members of the binds, so there's possibly a small memory leak here
• If we assign mib_ii_name_ptr directly to name.ids without cleaning up some of these other issues, we risk a double-free and small memory leak

Changes:

• Changed bind_ptr->name.ids assignment to actually use the SnmpUtilMemAlloc allocated memory, rather than the static array sitting in stack, to satisfy requirements indicated by MSDN documentation
• Cleaned up the memory handling around this in general, so that we can just call SnmpUtilVarBindListFree and be done.

Testing:

• None at all; I don't have a great reproduction case, and I haven't actually tried compiling locally yet, as I'm waiting on the CMake branch to be merged.

This can probably be merged after some basic testing.

[xezon]

This is amazing. I am so happy to see that we will crush these bugs like flies.