The values created at initialization must always exist to use the
interface. Reading them again is confusing, and pointless.

More cleanups are coming in the next patch. Since I am not 100% certain,
moreover on BYT, (though I am extremely close to that) that there is no
need to leave the MMIO here, I wanted to make it a separate patch for
the bisectable 'just-in-case'
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>