fs: take the ACL checks to common code

Replace the ->check_acl method with a ->get_acl method that simply reads an
ACL from disk after having a cache miss.  This means we can replace the ACL
checking boilerplate code with a single implementation in namei.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/reiserfs/file.c b/fs/reiserfs/file.c
index c7156dc..ace6350 100644
--- a/fs/reiserfs/file.c
+++ b/fs/reiserfs/file.c
@@ -319,5 +319,5 @@
 	.listxattr = reiserfs_listxattr,
 	.removexattr = reiserfs_removexattr,
 	.permission = reiserfs_permission,
-	.check_acl = reiserfs_check_acl,
+	.get_acl = reiserfs_get_acl,
 };