io_uring: do sqo disable on install_fd error

WARNING: CPU: 0 PID: 8494 at fs/io_uring.c:8717
	io_ring_ctx_wait_and_kill+0x4f2/0x600 fs/io_uring.c:8717
Call Trace:
 io_uring_release+0x3e/0x50 fs/io_uring.c:8759
 __fput+0x283/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x190 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

failed io_uring_install_fd() is a special case, we don't do
io_ring_ctx_wait_and_kill() directly but defer it to fput, though still
need to io_disable_sqo_submit() before.

note: it doesn't fix any real problem, just a warning. That's because
sqring won't be available to the userspace in this case and so SQPOLL
won't submit anything.

Reported-by:  <syzbot+9c9c35374c0ecac06516@syzkaller.appspotmail.com>
Fixes: d9d05217

 ("io_uring: stop SQPOLL submit on creator's death")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>