- malloc to ast_malloc
 - malloc + memset to ast_calloc
 - sizeof(struct foo) to sizeof(*bar)
 - remove indentation of the entire body of a function by returning immediately
   on an allocation failure
(issue #7581, tempest1)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@38088 65c4cc65-6c06-0410-ace0-fbb531ad65f3