ipc: Break IPC message channel to own files and general tidy of code
What actually happened:
copy src/xrt/ipc/shared/{ipc_utils.h => ipc_message_channel.h} (95%)
rename src/xrt/ipc/shared/{ipc_utils_unix.c => ipc_message_channel_unix.c} (99%)
rename src/xrt/ipc/shared/{ipc_utils_windows.cpp => ipc_message_channel_windows.cpp} (99%)
rewrite src/xrt/ipc/shared/ipc_utils.h (94%)
Edited by Jakob Bornecrantz