Follow on to @25796, with changes per review.
Original description:
mkrep.sh will no longer allow a standby replica to initially be
'mandtory' on startup, as required by p4d 2019.1.
If it was intended to be mandatory (i.e. has an 'ha' in the
ServerID), a new warning message id displayed describing why
that converting it to be mandatory should be considered after
it is caught up, and why.