pgsql: Fix handling of NULL return value in typarray lookup

Fix handling of NULL return value in typarray lookup

Commit 6ebeeae29 accidentally omitted testing the return value from
findTypeByOid which can return NULL. Fix by adding a check to make
sure that we have a pointer to dereference.

Author: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: /messages/by-id/CAEudQAqfMTH8Ya_J6E-NW_y_JyDFDxtQ4V_g6nY_1=0oDbQqdg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/85837b8037ada19d319fa4d3ba99c72205868199

Modified Files
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src/bin/pg_dump/pg_dump.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)