pgsql: Fix ordering of GRANT commands in pg_dumpall for tablespaces

Fix ordering of GRANT commands in pg_dumpall for tablespaces

This uses a method similar to 68a7c24f and now b8c6014 (applied for
database creation), which guarantees that GRANT commands using the WITH
GRANT OPTION are dumped in a way so as cascading dependencies are
respected.  Note that tablespaces do not have support for initial
privileges via pg_init_privs, so the same method needs to be applied
again.  It would be nice to merge all the logic generating ACL queries
in dumps under the same banner, but this requires extending the support
of pg_init_privs to objects that cannot use it yet, so this is left as
future work.

Discussion: https://postgr.es/m/20190522071555.GB1278@paquier.xyz
Author: Michael Paquier
Reviewed-by: Nathan Bossart
Backpatch-through: 9.6

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a7b2fca15b2552e004c9c1af2bbf07d0d8ef7a8b

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