LU-6401 uapi: turn lustre_param.h into a proper UAPI header

LU-6401 uapi: turn lustre_param.h into a proper UAPI header

Move all the kernel specific function prototypes from
lustre_param.h into obd_config.h which is a kernel only
header. The inline functions lustre_is_*_valid are used
only by user land so we can remove them. Remove the user
land error checking with lustre_is_*_valid() since its
the job of the kernel to validate the date passed in.
The libcfs.h header shouldn't be exposed to user land
so remove it.

Change-Id: I6b6b4fe8f4d6799608c0e74318afecb85168ad54
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/24325
Tested-by: Jenkins
Reviewed-by: Ben Evans <bevans@cray.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>