[arch-dev-public] mesa 7.5 is in testing

I've put mesa 7.5, xorg-server 1.6.2, xf86-video-intel 2.7.99.902 and a rebuild/update of all drivers containing DRI drivers in testing. The nouveau package was modified to use the latest version of libdrm instead of building from git, as the libdrm version is actually git master at this moment. I haven't included Radeon Gallium3D support yet, but we might put this into testing in a later stage. The libdrm package contains all the required libraries and changes for this. Please give these packages a test, so we can move them to extra soon.