pgsql: Fix volatile vs. pointer confusion

Fix volatile vs. pointer confusion

Variables used after a longjmp() need to be declared volatile. In
case of a pointer, it's the pointer itself that needs to be declared
volatile, not the pointed-to value. So we need

PyObject *volatile items;

instead of

volatile PyObject *items; /* wrong */

Discussion: https://www.postgresql.org/message-id/flat/f747368d-9e1a-c46a-ac76-3c27da32e8e4%402ndquadrant.com

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a1e9508b964155a81ec9a8e6e12be76796d47097

Modified Files
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contrib/hstore_plpython/hstore_plpython.c | 9 ++++-----
contrib/jsonb_plpython/jsonb_plpython.c | 9 +++------
2 files changed, 7 insertions(+), 11 deletions(-)