commit adc60298 upstream.

The xDC field should have 5 bit width according to Reference Manual.
Thus this patch fixes it.
Signed-off-by: Aurelien BOUIN <a_bouin@yahoo.fr>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>