mmc: msm_sdcc: Remove support for legacy msm_sdcc driver

Qualcomm's Secure Digitial Host Controller supports the standard host
controller interface (SDHCI). Remove msm_sdcc driver that supports
MCI interface.

Change-Id: Id6564330cf9a089b08f9c5ecbb5344d5bfc5ee5b
Signed-off-by: Venkat Gopalakrishnan <venkatg@codeaurora.org>