phy: starfive: Add mipi dphy tx support

Add mipi dphy tx support for the StarFive JH7110 SoC.
It is a module which is used to receive data from DSI
driver and transfer data to DSI interface like mipi screen.

Signed-off-by: Shengyang Chen <shengyang.chen@starfivetech.com>
Reviewed-by: Changhuang Liang <changhuang.liang@starfivetech.com>
Link: https://lore.kernel.org/r/20240418035020.47876-3-shengyang.chen@starfivetech.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>