pgsql: psql: have \d show FKs on partitioned tables

psql: have \d show FKs on partitioned tables

Commit 3de241dba86f missed to update psql to display foreign keys on
partitioned tables.  Add that.

Reported-by: Amit Langote
Author: Amit Langote
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/a66879e5-636f-d4dd-b4a4-92bdca5a828f@lab.ntt.co.jp

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/93316299d6a185bed0a4be5376508fe2f7e6b2d6

Modified Files
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src/bin/psql/describe.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)