pgsql: Fix query cancellation.

Fix query cancellation.

In commit fe0a0b59, the datatype used for MyCancelKey and other variables
that store cancel keys were changed from long to uint32, but I missed this
one. That broke query cancellation on platforms where long is wider than 32
bits.

Report by Andres Freund, fix by Michael Paquier.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/81f2e514a9b2d813bb5fd6b62523757aa7a6517f

Modified Files
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src/backend/postmaster/postmaster.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)