[EventPipe] Fix linker warning on Debug/Checked build and unlink Unix Domain Socket...

[EventPipe] Fix linker warning on Debug/Checked build and unlink Unix Domain Socket #23334 (#23357)

- Attempt to close-behind unix domain socket and repurpose LF_REMOTING facility.
  - On shutdown, attempt to unlink the bound socket so it can be removed from the file system when the last reference to it it closed.
- Rename unused LF_REMOTING to LF_DIAGNOSTICS_PORT. This new flag will be used by the diagnostic server stress log calls.
- libcmtd.lib(initializers.obj) : warning LNK4098: defaultlib 'libcmt.lib' conflicts with use of other libs; use /NODEFAULTLIB:library [S:\github.com\jorive\coreclr\bin\obj\Windows_NT.x64.Checked\src\dlls\mscoree\coreclr\coreclr.vcxproj]
- Move some preprocessors and includes around.