Ticket 48970 - Serverside sorting crashes the server
Bug Description: When using a matching rule and server side sorting
the server does a double-free on the matching rule
keys which crashes the server.
Fix Description: Set the pblock pointer to NULL after the keys are
freed. This prevents the double free.
Also fixed some complier warnings/indentation.
Valgrind: passed
https://fedorahosted.org/389/ticket/48970
Reviewed by: nhosoi(Thanks!)
(cherry picked from commit 43997fa8782ca93e20595ae10e303d85e5b765f4)