For SDCC version 5.0.0, MCI registers are removed from SDCC interface
and some registers are moved to HC. So add support to use the new
compatible string "qcom,sdhci-msm-v5". Based on this new msm variant,
pick the relevant variant data and use it to detect MCI presence thereby
configuring register read/write to msm specific registers.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Reviewed-by: Ramon Fried <rfried.dev@gmail.com>