pgsql: process startup: Do InitProcess() at the same time regardless of

process startup: Do InitProcess() at the same time regardless of EXEC_BACKEND.

An upcoming patch splits single user mode into its own function. This makes
that easier. Split out for easier review / testing.

Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: /messages/by-id/20210802164124.ufo5buo4apl6yuvs@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3d7c752a2f092b9f6581497009eacd10cab90548

Modified Files
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src/backend/postmaster/postmaster.c | 9 +++++++++
src/backend/tcop/postgres.c | 17 +++++------------
2 files changed, 14 insertions(+), 12 deletions(-)