mmc: sdhci-cadence: Update PHY delay configuration

DTS properties are used instead of fixed data
because PHY settings can be different for different chips/boards.

Signed-off-by: Piotr Sroka <piotrs@cadence.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>