media: rkisp1: add Rockchip MIPI Synopsys DPHY driver

This commit adds a subdev driver for Rockchip MIPI Synopsys DPHY driver

Signed-off-by: Jacob Chen <jacob2.chen@rock-chips.com>
Signed-off-by: Shunqian Zheng <zhengsq@rock-chips.com>
Signed-off-by: Tomasz Figa <tfiga@chromium.org>
[migrate to phy framework]
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
[update for upstream]
Signed-off-by: Helen Koike <helen.koike@collabora.com>

Series-changes: 7
- Migrate dphy specific code from
drivers/media/platform/rockchip/isp1/mipi_dphy_sy.c
to drivers/phy/rockchip/phy-rockchip-dphy.c
- Drop support for rk3288
- Drop support for dphy txrx
- code styling and checkpatch fixes