staging: lustre: remove LPF64 #define

Just use the proper string for the variable type.

Also remove some variable types that are not used at all (LPO64 and
LPPID)

Cc: Andreas Dilger <andreas.dilger@intel.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>