mmc: sdhci-sprd: Wait until DLL locked after being configured

According to the specification, DLL status has to be locked before using it.

Signed-off-by: Zhenxiong Lai <zhenxiong.lai@unisoc.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210926092835.146449-1-zhang.lyra@gmail.com


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