pgsql: Use int64 instead of long in incremental sort code

Use int64 instead of long in incremental sort code

Windows 64bit has 4-byte long values which is not suitable for tracking
disk space usage in the incremental sort code. Let's just make all these
fields int64s.

Author: James Coleman
Discussion: https://postgr.es/m/CAApHDvpky%2BUhof8mryPf5i%3D6e6fib2dxHqBrhp0Qhu0NeBhLJw%40mail.gmail.com
Backpatch-through: 13, where the incremental sort code was added

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/22c105595fc736ae94ce3b806da16b0bd8e94fb8

Modified Files
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src/backend/commands/explain.c | 20 ++++++++++----------
src/include/nodes/execnodes.h  |  8 ++++----
src/include/utils/tuplesort.h  |  2 +-
3 files changed, 15 insertions(+), 15 deletions(-)