pgsql: Fix ordering of GRANT commands in pg_dumpall for database creati

Fix ordering of GRANT commands in pg_dumpall for database creation

This uses a method similar to 68a7c24f, which guarantees that GRANT
commands using the WITH GRANT OPTION are dumped in a way so as cascading
dependencies are respected. As databases do not have support for
initial privileges via pg_init_privs, we need to repeat again the same
ACL reordering method.

ACL for databases have been moved from pg_dumpall to pg_dump in v11, so
this impacts pg_dump for v11 and above, and pg_dumpall for v9.6 and
v10.

Discussion: https://postgr.es/m/15788-4e18847520ebcc75@postgresql.org
Author: Nathan Bossart
Reviewed-by: Haribabu Kommi
Backpatch-through: 9.6

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a21fb12e7cc3e5ef976a384e7e7295d7e9b7460d

Modified Files
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src/bin/pg_dump/pg_dumpall.c | 33 ++++++++++++++++++++++++++-------
1 file changed, 26 insertions(+), 7 deletions(-)