pgsql: Fix local-variable shadowing in pg_trgm's printSourceNFA().

Fix local-variable shadowing in pg_trgm's printSourceNFA().

We hadn't noticed this violation of -Wshadow=compatible-local
because this function isn't compiled without -DTRGM_REGEXP_DEBUG.

As long as we have to clean it up, let's do so by converting all
this function's loops to use C99 loop-local control variables.

Reported-by: Sergei Kornilov <sk(at)zsrv(dot)org>
Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/3009911772478436@08341ecb-668d-43a9-af4d-b45f00c72521

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cdaa67565867ba443afb66b9e82023d65487dc7c

Modified Files
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contrib/pg_trgm/trgm_regexp.c | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)