qmp: Fix up comments after commit 9ce44e2ce2

Commit 9ce44e2ce2 "qmp: Move dispatcher to a coroutine" replaced
monitor_qmp_bh_dispatcher() by monitor_qmp_dispatcher_co(), but
neglected to update comments.  Do that now.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210201161504.1976989-2-armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
1 file changed