xfs: zero allocation_args on the kernel stack

Zero the kernel stack space that makes up the xfs_alloc_arg structures.

Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c
index 445bf1a..c5c4ef4 100644
--- a/fs/xfs/xfs_ialloc.c
+++ b/fs/xfs/xfs_ialloc.c
@@ -250,6 +250,7 @@
 					/* boundary */
 	struct xfs_perag *pag;
 
+	memset(&args, 0, sizeof(args));
 	args.tp = tp;
 	args.mp = tp->t_mountp;