dt-bindings: mmc: sdhci-of-dwcmhsc: Add compatible string for RK3528

The SDHCI controller in Rockchip RK3528 is similar to the one included
in RK3588.

Add compatible string for the SDHCI controller in RK3528.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250305214108.1327208-2-jonas@kwiboo.se


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>