mmc: host: sdhci-msm-ice: Support for clearing ice configuration

Adding support for clearing ice configuration.
Once mmc request processing is completed, mmc driver has to
call config_end to ensure key information is cleared by ICE
driver. This call is optional for FDE but required for FBE.

Change-Id: I8c225deda782528a7f220f7d1f81c6240caca1ae
Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>