mmc: msm_sdcc: Rename config MMC_MSM7X00A to MMC_MSM

SD/MMC host controller driver is same for all MSM and QSD
platforms. Hence, rename the config to reflect the same.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>