Обсуждение: pgsql: Use NULL instead of 0 for 'arg' argument in dshash_create() call

Use NULL instead of 0 for 'arg' argument in dshash_create() calls.

A couple of dshash_create() callers provide 0 for the 'void *arg'
argument, which might give readers the incorrect impression that
this is some sort of "flags" parameter.

Reviewed-by: Andy Fan
Discussion: https://postgr.es/m/20240119215941.GA1322079%40nathanxps13

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5fe08c006c826da4a7f5db2a79327477599edbc6

Modified Files
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src/backend/replication/logical/launcher.c | 2 +-
src/backend/utils/activity/pgstat_shmem.c  | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)