-Fix a few compiler warnings.

git-svn-id: http://odamex.net/svn/root/trunk@3842 b0bcef46-2027-0410-bd56-ab726e9a1d04
- Sync to miniupnpc-1.8.20130503

git-svn-id: http://odamex.net/svn/root/trunk@3843 b0bcef46-2027-0410-bd56-ab726e9a1d04