pgsql: Use hba_file/ident_file GUCs rather than pg_hba.conf/pg_ident.co

Use hba_file/ident_file GUCs rather than pg_hba.conf/pg_ident.conf in logs

This is particularly useful when log_min_messages is set to FATAL, so as
one can know which file was not getting loaded whether hba_file or
ident_file are set to some non-default values.  If using the default
values of these GUC parameters, the same reports are generated.

This commit changes the load (startup) and reload (SIGHUP) messages.

Author: Julien Rouhaud
Discussion: https://postgr.es/m/20220223045959.35ipdsvbxcstrhya@jrouhaud

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/47ab1ac822cd928bfe43b2c25be102a6a08902f4

Modified Files
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src/backend/postmaster/postmaster.c | 7 ++++---
src/backend/utils/init/postinit.c   | 3 ++-
2 files changed, 6 insertions(+), 4 deletions(-)