GFS2: use _RET_IP_ instead of (unsigned long)__builtin_return_address(0)

use macro definition

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 7f513b1..8f0c19d 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -811,7 +811,7 @@
 {
 	INIT_LIST_HEAD(&gh->gh_list);
 	gh->gh_gl = gl;
-	gh->gh_ip = (unsigned long)__builtin_return_address(0);
+	gh->gh_ip = _RET_IP_;
 	gh->gh_owner_pid = get_pid(task_pid(current));
 	gh->gh_state = state;
 	gh->gh_flags = flags;
@@ -835,7 +835,7 @@
 	gh->gh_state = state;
 	gh->gh_flags = flags;
 	gh->gh_iflags = 0;
-	gh->gh_ip = (unsigned long)__builtin_return_address(0);
+	gh->gh_ip = _RET_IP_;
 	if (gh->gh_owner_pid)
 		put_pid(gh->gh_owner_pid);
 	gh->gh_owner_pid = get_pid(task_pid(current));