lmtp proxy: Don't internally finish proxying before client has even sent DATA command. This fixes some crashes when all recipients were invalid.
lmtp proxy: Don't internally finish proxying before client has even sent DATA command.
This fixes some crashes when all recipients were invalid.

LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot