mmc: dw_mmc-rockchip: Add support for rk3576 SoCs

mmc: dw_mmc-rockchip: Add support for rk3576 SoCs

On rk3576 the tunable clocks are inside the controller itself, removing
the need for the "ciu-drive" and "ciu-sample" clocks.

That makes it a new type of controller that has its own dt_parse function.

Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/010201919997044d-c3a008d1-afbc-462f-a928-fc1ece785bdb-000000@eu-west-1.amazonses.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>