tomoyo: don't special case PF_IO_WORKER for PF_KTHREAD

Since commit 3bfe6106 ("io-wq: fork worker threads from original
task") stopped using PF_KTHREAD flag for the io_uring PF_IO_WORKER threads,
tomoyo_kernel_service() no longer needs to check PF_IO_WORKER flag.

(This is a 5.12+ patch. Please don't send to stable kernels.)
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

security/tomoyo/network.c

@@ -613,7 +613,7 @@ static int tomoyo_check_unix_address(struct sockaddr *addr,
 static bool tomoyo_kernel_service(void)
 {
 	/* Nothing to do if I am a kernel service. */
-	return (current->flags & (PF_KTHREAD | PF_IO_WORKER)) == PF_KTHREAD;
+	return current->flags & PF_KTHREAD;
 }
 
 /**