Use plain "pgrep" in rc script to accommodate different path in DragonFly.
Reported by: Juan Francisco Cantero Hurtado <iam@juanfra.info>

Update to 5.7p4. No user-visible changes.

In particular, the new HTTPS contraint feature is *not* enabled, because

• LibreSSL fails with the certificiate bundle from ca_root_nss
• USE_OPENSSL does not handle LibreSSL yet