xfs: remove incorrect error negation in attr_multi ioctl

xfs_compat_attrmulti_by_handle() calls memdup_user() which returns a
negative error code. The error code is negated by the caller and thus
incorrectly converted to a positive error code.

Remove the error negation such that the negative error is passed
correctly back up to userspace.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
index ec67728..bfc7c7c 100644
--- a/fs/xfs/xfs_ioctl32.c
+++ b/fs/xfs/xfs_ioctl32.c
@@ -423,7 +423,7 @@
 
 	ops = memdup_user(compat_ptr(am_hreq.ops), size);
 	if (IS_ERR(ops)) {
-		error = -PTR_ERR(ops);
+		error = PTR_ERR(ops);
 		goto out_dput;
 	}