io_uring: make fallocate be hashed work

Like ftruncate and write, fallocate operations on the same file cannot
be executed in parallel, so it is better to make fallocate be hashed
work.

Signed-off-by: Fengnan Chang <changfengnan@bytedance.com>
Link: https://lore.kernel.org/r/20250623110218.61490-1-changfengnan@bytedance.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>