pgsql: Mark advisory-lock functions as parallel restricted, not paralle

Mark advisory-lock functions as parallel restricted, not parallel unsafe.

There seems no good reason not to allow a parallel leader to execute
these functions. (The workers still can't, though. Although the code
would work, any such lock would go away at worker exit, which is not
the documented behavior of advisory locks.)

Discussion: https://postgr.es/m/11847.1564496844@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4886da8327507dddd830786b0c7aaa9cfc480b4b

Modified Files
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src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_proc.dat | 42 ++++++++++++++++++++--------------------
2 files changed, 22 insertions(+), 22 deletions(-)