pgsql: Force creation of stamp file after libpq library check in meson

Force creation of stamp file after libpq library check in meson builds

Previously, if --stamp_file was specified, libpq_check.pl would create a
new stamp file only if none could be found. If there was already a
stamp file, the script would do nothing, leaving the previous stamp file
in place. This logic could cause unnecessary rebuilds because meson
relies on the timestamp of the output files to determine if a rebuild
should happen. In this case, a stamp file generated during an older
check would be kept, but we need a stamp file from the latest moment
where the libpq check has been run, so as correct rebuild decisions can
be taken.

This commit changes libpq_check.pl so as a fresh stamp file is created
each time libpq_check.pl is run, when --stamp_file is specified.

Oversight in commit 4a8e6f43a6b5.

Reported-by: Andres Freund <andres(at)anarazel(dot)de>
Author: Nazir Bilal Yavuz <byavuz81(at)gmail(dot)com>
Reviewed-by: VASUKI M <vasukim1992002(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAN55FZ22rrN6gCn7urtmTR=_5z7ArZLUJu-TsMChdXwmRTaquA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/623a90c2ade60ae52bf19495d8670c9b72de4299

Modified Files
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src/interfaces/libpq/libpq_check.pl | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)