fixes some memory leaks and redundant conditions

(closes issue #15269)
Reported by: contactmayankjain
Patches:
      patch.txt uploaded by contactmayankjain (license 740)
      memory_leak_stuff.trunk.diff uploaded by dvossel (license 671)
Tested by: contactmayankjain, dvossel




git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@201678 65c4cc65-6c06-0410-ace0-fbb531ad65f3