staging/lustre: Get rid of C99 comments in lustre_idl.h

lustre_idl.h contains various protocol data. In order to avoid
reusal of values that might have meant something else in the past,
the old no longer used values are commented out, convert the
comments into regular comments from C99 where appropriate.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>