Code beautification for object-access hook machinery.

src/backend/catalog/Makefile

src/backend/catalog/dependency.c

src/backend/catalog/heap.c

src/backend/catalog/index.c

src/backend/catalog/objectaccess.c

src/backend/catalog/pg_collation.c

src/backend/catalog/pg_constraint.c

src/backend/catalog/pg_conversion.c

src/backend/catalog/pg_namespace.c

src/backend/catalog/pg_operator.c

src/backend/catalog/pg_proc.c

src/backend/catalog/pg_type.c

src/backend/commands/aggregatecmds.c

src/backend/commands/dbcommands.c

src/backend/commands/event_trigger.c

src/backend/commands/extension.c

src/backend/commands/foreigncmds.c

src/backend/commands/functioncmds.c

src/backend/commands/opclasscmds.c

src/backend/commands/proclang.c