phy: hdmi: Add color depth configuration

Extend the HDMI configuration options to allow managing bits per color
channel. This is required by some PHY drivers such as
rockchip-samsung-hdptx.

Reviewed-by: Dmitry Baryshkov <[e-mail]>
Signed-off-by: Cristian Ciocaltea <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

include/linux/phy/phy-hdmi.h

···
 /**
  * struct phy_configure_opts_hdmi - HDMI configuration set
  * @tmds_char_rate: HDMI TMDS Character Rate in Hertz.
+ * @bpc: Bits per color channel.
  *
  * This structure is used to represent the configuration state of a HDMI phy.
  */
 struct phy_configure_opts_hdmi {
 	unsigned long long tmds_char_rate;
+	unsigned int bpc;
 };
 
 #endif /* __PHY_HDMI_H_ */