LU-6401 uapi: fix up lustre_ostid.h and lustre_fid.h

LU-6401 uapi: fix up lustre_ostid.h and lustre_fid.h

Several inline functions in the header lustre_ostid.h
are using debug macros instead of returning proper errors.
Remove the debug macros and properly handle the returned
error codes. Place both UAPI headers lustre_fid.h and
lustre_ostid.h into the uapi directory.

Change-Id: Ic32afd05850b5bf02fb8de655cb1971eeb52a321
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/24569
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Tested-by: Oleg Drokin <oleg.drokin@intel.com>