scylla-gdb: scylla_io_queues: support io_group._max_bytes_count
scylla-gdb: scylla_io_queues: support io_group._max_bytes_count

_maximum_request_size is renamed to _max_bytes_count
in https://github.com/scylladb/seastar/commit/40a29d55905b0aa60d988c299a7cb26f9f6c8323

This patch adds support for ioq io_group._max_bytes_count
if io_group._maximum_request_size isn't found.

Test: scylla-gdb(release)
Signed-off-by: Benny Halevy <23c997c90eb8537635e9392d48e7af1bf1b2ca22@scylladb.com>
Message-Id: <20210520151537.710123-1-23c997c90eb8537635e9392d48e7af1bf1b2ca22@scylladb.com>

scylladb/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla