Implemented sceGeGetMtx for the external software renderer

git-svn-id: http://jpcsp.googlecode.com/svn/trunk@3669 4ab978e6-3352-0410-996c-0b42db0051c8
Small compatibility improvement for sceAtracReinit

git-svn-id: http://jpcsp.googlecode.com/svn/trunk@3670 4ab978e6-3352-0410-996c-0b42db0051c8
Improvement of sceMpegGetUserdataAu

git-svn-id: http://jpcsp.googlecode.com/svn/trunk@3671 4ab978e6-3352-0410-996c-0b42db0051c8