Btrfs: remove OPT_acl parse when acl disabled

Even CONFIG_BTRFS_FS_POSIX_ACL is not defined, the acl still could
been enabled using a mount option, and now fs/btrfs/acl.o is not
built, so the mount options will appear to be supported but will
be silently ignored.

Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>

fs/btrfs/super.c

@@ -580,8 +580,15 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
 			}
 			break;
 		case Opt_acl:
+#ifdef CONFIG_BTRFS_FS_POSIX_ACL
 			root->fs_info->sb->s_flags |= MS_POSIXACL;
 			break;
+#else
+			btrfs_err(root->fs_info,
+				"support for ACL not compiled in!");
+			ret = -EINVAL;
+			goto out;
+#endif
 		case Opt_noacl:
 			root->fs_info->sb->s_flags &= ~MS_POSIXACL;
 			break;