ocfs2: potential ERR_PTR dereference on error paths

If "handle" is non null at the end of the function then we assume it's a
valid pointer and pass it to ocfs2_commit_trans();

Signed-off-by: Dan Carpenter <error27@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index ab20790..23c254e 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -559,6 +559,7 @@
 		handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
 		if (IS_ERR(handle)) {
 			status = PTR_ERR(handle);
+			handle = NULL;
 			mlog_errno(status);
 			goto out;
 		}