staging: lustre: ldlm: remove commented call to LBUG

This patch removes a commented call to LBUG since lustre should be
cleaned out of debugging macros before moving out of staging.

Signed-off-by: Aya Mahfouz <mahfouz.saif.elyazal@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>