pgsql: Fix another test for RELKIND_RELATION that should allow foreign

Fix another test for RELKIND_RELATION that should allow foreign tables now.

I thought I'd gone through all of these before, but a fresh review found
this one too.  (Perhaps it would be better to just delete this test and
let the failure occur later, but for the moment I'll preserve the logic.)

The case that this was rejecting is like
    CREATE FOREIGN TABLE ft (f1 int ...) ...;
    CREATE TABLE c1 (UNIQUE(f1)) INHERITS(ft);

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/290713e31a1ee04eed7877985a4c28a30fd0d1db

Modified Files
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src/backend/parser/parse_utilcmd.c |    6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)