pgsql: Remove obsolete comment and code from fe-auth.c.

Remove obsolete comment and code from fe-auth.c.

We don't use getpwuid() anymore (see commit e757cdd6), so we don't need
locking around pg_get_user_name().

Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/CA%2BhUKGLtmexrpMtxBRLCVePqV_dtWG-ZsEbyPrYc%2BNBB2TkNsw%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1aadc504bf47ade96178b98fe80803f244c1ee28

Modified Files
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src/interfaces/libpq/fe-auth.c | 11 -----------
1 file changed, 11 deletions(-)