pgsql: Report a more useful error for reloptions on a partitioned table

Report a more useful error for reloptions on a partitioned table.

Previously, trying to set storage parameters on a partitioned table
always led to "unrecognized parameter foo", because the code expected
there might be some valid parameters; but there aren't any.  The docs
make clear that it's intended that there never will be any, so let's
replace this useless search with a more to-the-point message.

Simon Riggs and Karina Litskevich

Discussion: https://postgr.es/m/CANbhV-H=eZ9kTR9mUgKGK0Qv9uXP=U+dQg3rinQHfTdFMhBA2A@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4f981df8e0b7bc00d22ab0db65579589c9d4bb8c

Modified Files
--------------
src/backend/access/common/reloptions.c     | 13 ++++++-------
src/test/regress/expected/alter_table.out  |  4 ++++
src/test/regress/expected/create_table.out |  4 ++++
src/test/regress/sql/alter_table.sql       |  3 +++
src/test/regress/sql/create_table.sql      |  3 +++
5 files changed, 20 insertions(+), 7 deletions(-)