[radeonhd] RFC: Porting radeonhds HDMI support to KMS

Hi everybody, since i didn't got so much todo in the last week than i thought i would, i finally sit down and ported the HDMI support for R600 and up chipsets from radeonhd to KMS. So the attached patch is based on Dave Airlies drm-next tree (http://git.kernel.org/?p=linux/kernel/git/airlied/drm-2.6.git;a=shortlog;h=d...). It's been a while since i last coded inside kernel space and the patch is not very well tested, so there are quite a bunch of "TODO"s inside the code, but at least it's a starting point and seems to work fine with the radeon driver+KMS. So any comments or test results would be very welcome. Bye, Christian.