pgsql: Allow makeaclitem() to accept multiple privilege names.

Allow makeaclitem() to accept multiple privilege names.

Interpret its privileges argument as a comma-separated list of
privilege names, as in has_table_privilege and other functions.
This is actually net less code, since the support routine to
parse that already exists, and we can drop convert_priv_string()
which had no other use-case.

Robins Tharakan

Discussion: https://postgr.es/m/e5a05dc54ba64408b3dd260171c1abaf@EX13D05UWC001.ant.amazon.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b762bbde30d21d6a091d44cc2cbbfb1c9550be52

Modified Files
--------------
doc/src/sgml/func.sgml                   |  9 ++++-
src/backend/utils/adt/acl.c              | 66 ++++++++++----------------------
src/test/regress/expected/privileges.out | 18 +++++++++
src/test/regress/sql/privileges.sql      |  8 ++++
4 files changed, 54 insertions(+), 47 deletions(-)