pgsql: Suppress platform-dependent unused-variable warning.

Suppress platform-dependent unused-variable warning.

The local variable "sock" can be unused depending on compilation flags.
But there seems no particular need for it, since the kernel calls can
just as easily say port->sock instead.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/82e4d45bd0ba9c07b8a97f28f939db6d8d564f9a

Modified Files
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src/backend/libpq/auth.c |    9 ++++-----
1 files changed, 4 insertions(+), 5 deletions(-)