Fix some compilation warnings in the Squeak3D plugin (thanks Nicolas!).


git-svn-id: http://squeakvm.org/svn/squeak/trunk/platforms/Cross/plugins@3004 fa1542d4-bde8-0310-ad64-8ed1123d492a
and remember to update sqPluginsSCCSVersion.h


git-svn-id: http://squeakvm.org/svn/squeak/trunk/platforms/Cross/plugins@3005 fa1542d4-bde8-0310-ad64-8ed1123d492a