pgsql: Prevent stack overflow in query-type functions.

Prevent stack overflow in query-type functions.

The tsquery, ltxtquery and query_int data types have a common ancestor.
Having acquired check_stack_depth() calls independently, each was
missing at least one call.  Back-patch to 9.0 (all supported versions).

Branch
------
REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/7bed97d486bda5761ba7e7982e4133aeded6b852

Modified Files
--------------
contrib/intarray/_int_bool.c            |    3 +++
contrib/ltree/ltxtquery_io.c            |    3 +++
contrib/ltree/ltxtquery_op.c            |    4 ++++
src/backend/utils/adt/tsquery_cleanup.c |    3 +++
4 files changed, 13 insertions(+)