pgsql: Add a couple of missing FreeQueryDesc calls.

Log Message:
-----------
Add a couple of missing FreeQueryDesc calls. Noticed while testing a
framework to keep track of snapshots in use.

Modified Files:
--------------
pgsql/src/backend/commands:
portalcmds.c (r1.69 -> r1.70)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/portalcmds.c?r1=1.69&r2=1.70)
pgsql/src/backend/executor:
spi.c (r1.188 -> r1.189)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/executor/spi.c?r1=1.188&r2=1.189)