pgsql: Simplify code to switch pg_class.relrowsecurity in tablecmds.c

Simplify code to switch pg_class.relrowsecurity in tablecmds.c

The same code pattern was repeated twice to enable or disable ROW LEVEL
SECURITY with an ALTER TABLE command. This makes the code slightly
cleaner.

Author: Justin Pryzby
Reviewed-by: Zhihong Yu
Discussion: /messages/by-id/20210228211854.GC20769@telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/fabde52fab976ff782d77c80b8e2614f94f9dce1

Modified Files
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src/backend/commands/tablecmds.c | 34 +++++-----------------------------
1 file changed, 5 insertions(+), 29 deletions(-)