media: sony-cxd2880: add optional vcc regulator to bindings

This patchset adds an optional VCC regulator to the bindings of the Sony
CXD2880 DVB-T2/T tuner + demodulator adapter.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Yasunari Takiguchi <Yasunari.Takiguchi@sony.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>