pgsql-server: Fix some typos I introduced in WIN32-only code late last

Log Message:
-----------
Fix some typos I introduced in WIN32-only code late last night.
Thanks to Thomas Hallgren.

Modified Files:
--------------
pgsql-server/src/backend/postmaster:
postmaster.c (r1.398 -> r1.399)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/postmaster/postmaster.c.diff?r1=1.398&r2=1.399)