test/send_recv: test non-registered SQPOLL files if available
test/send_recv: test non-registered SQPOLL files if available

Repeat the SQPOLL test case, but with non-registered files, if
IORING_FEAT_SQPOLL_NONFIXED is available.

Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>

axboe/liburing,axboe/liburing,axboe/liburing