pgsql: Remove last traces of --adduser/--no-adduser in createuser

Remove last traces of --adduser/--no-adduser in createuser

8ae0d47 marked those options as obsolete back in 2005, with the options
removed from the documentation.  This removes the last references to
both options in the code which were kept around for compatibility
purposes with past commands.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/5da284a2-62d9-e338-88d1-26ee5009d93e@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4fa5edcd1a45cb11bc52b612e12bb29ab39cb895

Modified Files
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src/bin/scripts/createuser.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)