Give the "DFP 1.x" bit a proper name, and clean up the rest
of the bits defines as well.

Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190529110204.2384-1-ville.syrjala@linux.intel.comReviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NMario Kleiner <mario.kleiner.de@gmail.com>