test/accept: clean code of accept test
test/accept: clean code of accept test

This does three things:
 - change multishot_mask from uint to uint32_t
 - change multishot_mask != UINT_MAX check to ~multishot_mask != 0

The above two avoid compiler and arch influence. Make the logic more robost.

 - other cleaning to make code clearer.

Signed-off-by: Hao Xu <83f1fd80049157f4783893e94b7e479a9ba8b984@tencent.com>
Link: fe56b2f0d85b0fb75d85025cf38628fc9c353655@linux.dev
Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>

axboe/liburing,axboe/liburing,axboe/liburing