Radeon & TMDS_PLL_CNTL hack

[Benjamin Herrenschmidt]

> Looking back through CVS history, it looks like it came straight from
> Hui Yu like that.

Yup, though it's also my understanding that at that time Hui, worked
with pre-production rv280's (that's also why version 4 BIOS TMDS info
blocks are not currently used in the driver, they had "issues" on those
pre-production cards Hui was using). I'm wondering if we can "fix" that
now. From my experience, so far at least, the cards I've seen have a
valid block versio 4 and my rv280 need the "commented" value ...

Ben.