Include path inconsistencies

[santaclose]

Includes for files under include/PR seem to be inconsistent, sometimes doing #include <PR/filename.h>, and sometimes #include <filename.h>.

For example, in:
https://github.com/decompals/ultralib/blob/main/src/sp/sprite.c

I see:
#include <sp.h>
#include <PR/os_version.h>

being both sp.h and os_version.h under include/PR

I don't know if this is the case with other folders in the include directory.