osd/PeeringState: do not check for require_osd_release

osd/PeeringState: do not check for require_osd_release

before this change, we always check for require_osd_release when
creating MOSDPGNotify2 or MOSDPGNotify, if require_osd_release is
greater or equal to octopus, MOSDPGNotify2 is created.

since we are in a post-quincy era, and we only need to upgrade from
octopus and up to quincy, there is no need to be compatible with
osd whose version is lower than octopus.

in this change, the check in `BufferedRecoveryMessages::send_notify()`
is dropped.

Signed-off-by: Kefu Chai <kchai@redhat.com>