Get "no acls for this inode" right, fix shmem breakage

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index c513466..065a365 100644
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -148,4 +148,13 @@
 		posix_acl_release(old);
 }
 #endif
+
+static inline void cache_no_acl(struct inode *inode)
+{
+#ifdef CONFIG_FS_POSIX_ACL
+	inode->i_acl = NULL;
+	inode->i_default_acl = NULL;
+#endif
+}
+
 #endif  /* __LINUX_POSIX_ACL_H */