gfs-kernel: bug 450209 - addendum to previous patch. Removes extraneous lock_dlm_plock.c
gfs-kernel: bug 450209 - addendum to previous patch. Removes extraneous lock_dlm_plock.c

I accidentally added this file to the patch I posted earlier to this bug. It's just
an extra file at this point; Makefile doesn't even compile it. This commit removes it.

asp24/resource-agents,stevenraspudic/resource-agents,stevenraspudic/resource-agents,asp24/resource-agents,asp24/resource-agents,stevenraspudic/resource-agents