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_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c77f21899ac2bd85d9d30d2dbf60904498ebee2f

Modified Files
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contrib/hstore_plpython/hstore_plpython.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)