pgsql: pg_dump: Remove some unused return values.

pg_dump: Remove some unused return values.

getSchemaData() does not use the return values of many of its get*
helper functions because they store the data elsewhere. For
example, commit 92316a4582 introduced a separate hash table for
dumpable objects that said helper functions populate. This commit
changes these functions to return void and removes their "int *"
parameters that returned the number of objects found.

Reviewed-by: Neil Conway, Tom Lane, Daniel Gustafsson
Discussion: https://postgr.es/m/ZmCAtVaOrHpf31PJ%40nathan

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8213df9effaf0767efa7faf9b75fa500d4f45985

Modified Files
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src/bin/pg_dump/common.c | 69 ++++--------
src/bin/pg_dump/pg_dump.c | 282 +++++++++++-----------------------------------
src/bin/pg_dump/pg_dump.h | 49 ++++----
3 files changed, 113 insertions(+), 287 deletions(-)