Use the names more suitable for devicetree bindings.

There are no board files utilizing this, thus we seem to be at liberty
at renaming this without consequences.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>