pgsql: Make the order of operations in PostmasterMain a bit saner ...

Log Message:
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Make the order of operations in PostmasterMain a bit saner ... some
recent patches had added stuff in rather random spots.

Modified Files:
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pgsql/src/backend/postmaster:
postmaster.c (r1.495 -> r1.496)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/postmaster.c.diff?r1=1.495&r2=1.496)