[GFS2] fix GFP_KERNEL misuses

There are several places where GFP_KERNEL allocations happen under a glock,
which will result in hangs if we're under memory pressure and go to re-enter the
fs in order to flush stuff out.  This patch changes the culprits to GFS_NOFS to
keep this problem from happening.  Thank you,

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/locking/dlm/lock.c b/fs/gfs2/locking/dlm/lock.c
index 53a6ab3..cf7ea8a 100644
--- a/fs/gfs2/locking/dlm/lock.c
+++ b/fs/gfs2/locking/dlm/lock.c
@@ -165,7 +165,7 @@
 {
 	struct gdlm_lock *lp;
 
-	lp = kzalloc(sizeof(struct gdlm_lock), GFP_KERNEL);
+	lp = kzalloc(sizeof(struct gdlm_lock), GFP_NOFS);
 	if (!lp)
 		return -ENOMEM;
 
@@ -383,7 +383,7 @@
 {
 	char *lvb;
 
-	lvb = kzalloc(GDLM_LVB_SIZE, GFP_KERNEL);
+	lvb = kzalloc(GDLM_LVB_SIZE, GFP_NOFS);
 	if (!lvb)
 		return -ENOMEM;