kill check_acl callback of generic_permission()

its value depends only on inode and does not change; we might as
well store it in ->i_op->check_acl and be done with that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index 0a12eb8..a37165c 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -362,5 +362,5 @@
 	sysfs_refresh_inode(sd, inode);
 	mutex_unlock(&sysfs_mutex);
 
-	return generic_permission(inode, mask, flags, NULL);
+	return generic_permission(inode, mask, flags);
 }