pgsql: Remove compiler warning option -Wendif-labels

Remove compiler warning option -Wendif-labels

This warning has always been on by default in GCC (and in Clang at
least going back to 3.1), so we don't need the option explicitly.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/aa73q1aT0A3/vke/%40ip-10-97-1-34.eu-west-3.compute.internal

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/87e1891c459ecf7aa839de75d8afca3e1a6d154f

Modified Files
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configure    | 91 ------------------------------------------------------------
configure.ac |  2 --
meson.build  |  1 -
3 files changed, 94 deletions(-)