Bytecode API discrepancy: map_removekey return value

[micahsnyder]

Describe the bug

I discovered that the documentation for the bytecode API function map_remove lies. It says:

Returns
0 on success, key was present
1 if key was not present
<0 if ksize doesn’t match keysize specified at table creation

in truth it used to return whatever cli_map_removekey() returned in https://github.com/Cisco-Talos/clamav/blob/clamav-0.105.1/libclamav/bytecode_api.c#L1432-L1438,
and that used to return 0 if the key was not present, and 1 if the key was present and removed: https://github.com/Cisco-Talos/clamav/blob/clamav-0.105.1/libclamav/hashtab.c#L893-L914

I'm making this issue because we haven't converted the old doxygen docs to markdown, and we also don't have a way at present to re-generate the PDF user manual. So when we do the documentation overhaul for the compiler project, we ought to fix this discrepancy.