pgsql: Default to thread safety on, and support more CPU options.

Log Message:
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Default to thread safety on, and support more CPU options. Also
make sure that a CPU option is actually chosen.

Hiroshi Saito

Modified Files:
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pgsql/src/interfaces/libpq:
win32.mak (r1.48 -> r1.49)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/win32.mak?r1=1.48&r2=1.49)