pgsql: Add pid to the pgident event name on win32.

Log Message:
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Add pid to the pgident event name on win32.

Should fix a problem where two clusters are running under
two different service accounts and get colliding names,
causing only the first cluster to contain the pgident
event description.

Per report from Stephen Denne.

Tags:
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REL8_2_STABLE

Modified Files:
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pgsql/src/backend/utils/misc:
ps_status.c (r1.33 -> r1.33.2.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/ps_status.c?r1=1.33&r2=1.33.2.1)