Revert "postmaster: Start syslogger earlier".

Revert "postmaster: Start syslogger earlier".

This commit reverts 57431a911d3a650451d198846ad3194900666152.

While that's still a good idea in the abstract, we found out
that there are multiple crasher bugs in it on Windows builds,
making the logging_collector option unusable on Windows.
There's no time left to fix these issues before 12beta1,
so revert the patch to allow Windows beta testing to proceed.
We'll try again at some future date.

Per bug #15804 from Yulian Khodorkovskiy and additional
investigation by Michael Paquier.

Discussion: https://postgr.es/m/15804-3721117bf40fb654@postgresql.org