pgsql: Fix "Remove superfluous tqual.h includes" by adding back one inc

Fix "Remove superfluous tqual.h includes" by adding back one include.

I removed one include too many in e7cc78ad43eb, not sure why that
escaped my test script.

Author: Andres Freund

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/527114e51e45dbd91d46171fa4a111355f0dfc3b

Modified Files
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src/backend/catalog/catalog.c | 1 +
1 file changed, 1 insertion(+)