pgsql: Re-allow user_catalog_table option for materialized views.

Re-allow user_catalog_table option for materialized views.

The reloptions stuff allows this option to be set on a matview.
While it's questionable whether that is useful or was really intended,
it does work, and we shouldn't change that in minor releases. Commit
e3e66d8a9 disabled the option since I didn't realize that it was
possible for it to be set on a matview. Tweak the test to re-allow it.

Discussion: <19749(dot)1478711862(at)sss(dot)pgh(dot)pa(dot)us>

Branch
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REL9_6_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/05a6e872898acad6a66f9fd0be01e30ae1fb0f75

Modified Files
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src/include/utils/rel.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)