macOS: Put kvm debug messages behind compile option

[PTR-inc]

Summary

Also seen through the testing of the mac agent via terminal start.

As soon as a desktop session started, the console was flooded with dev debug messages. Put the already commented 'KvmDebugLog()' function in behind KVMDEBUGENABLED (enable through KVMDEBUG=1 in the make command) and replaced the debug messages with the the KvmDebugLog().
Default is off, so no more flooding.

The ...loop messages were send per frame, that were many

Example:
About to read from IPC Socket
...Enter for loop
Read 10 bytes from IPC-xx-Socket
enter while
exited while
About to read from IPC Socket
...exit for loop
...Enter for loop
...exit for loop
...Enter for loop
...exit for loop
...Enter for loop
...exit for loop
...Enter for loop
...exit for loop
...Enter for loop
...exit for loop
...Enter for loop

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Testing

Tested on macos arm64/x64