xfs: fix coccinelle warnings

Removes unneeded semicolon, introduced by commit a70a4fa5 ("xfs: fix
a couple error sequence jumps in xfs_mountfs"):

fs/xfs/xfs_mount.c:858:24-25: Unneeded semicolon

Generated by: scripts/coccinelle/misc/semicolon.cocci

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>