get rid of pointless checks for dentry->sb == NULL

it never is...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/cachefiles/bind.c

@@ -129,7 +129,6 @@ static int cachefiles_daemon_add_cache(struct cachefiles_cache *cache)
 	    !root->d_inode->i_op->mkdir ||
 	    !root->d_inode->i_op->setxattr ||
 	    !root->d_inode->i_op->getxattr ||
-	    !root->d_sb ||
 	    !root->d_sb->s_op ||
 	    !root->d_sb->s_op->statfs ||
 	    !root->d_sb->s_op->sync_fs)

security/tomoyo/realpath.c

@@ -103,7 +103,7 @@ char *tomoyo_realpath_from_path(struct path *path)
 		if (!buf)
 			break;
 		/* Get better name for socket. */
-		if (dentry->d_sb && dentry->d_sb->s_magic == SOCKFS_MAGIC) {
+		if (dentry->d_sb->s_magic == SOCKFS_MAGIC) {
 			struct inode *inode = dentry->d_inode;
 			struct socket *sock = inode ? SOCKET_I(inode) : NULL;
 			struct sock *sk = sock ? sock->sk : NULL;