pgsql: Send paramHandle to subprocesses as 64-bit on Win64

Send paramHandle to subprocesses as 64-bit on Win64

The handle to the shared memory segment containing startup
parameters was sent as 32-bit even on 64-bit systems. Since
HANDLEs appear to be allocated sequentially this shouldn't
be a problem until we reach 2^32 open handles in the postmaster,
but a 64-bit value should be sent across as 64-bit, and not
zero out the top 32 bits.

Noted by Tom Lane.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=d3f62f232fc874efb22a06b2fd370eefa5f62790

Modified Files
--------------
src/backend/postmaster/postmaster.c |    8 ++++++++
1 files changed, 8 insertions(+), 0 deletions(-)