io_uring/net: don't use io_net_kbuf_recyle() for non-provided cases
A previous commit used io_net_kbuf_recyle() for any network helper that
did IO and needed partial retry. However, that's only needed if the
opcode does buffer selection, which isnt support for sendzc, sendmsg_zc,
or sendmsg. Just remove them - they don't do any harm, but it is a bit
confusing when reading the code.
Link: https://lore.kernel.org/r/20250821020750.598432-4-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>