pgsql: Fix compiler warning

Fix compiler warning

Fix a warning about unused variable on Windows when using OpenSSL.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/36515e4f14fc1b22787a54d5de45b1e6b5e6cd9c

Modified Files
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src/port/pg_strong_random.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)