msm: Implement init_card operation for MSM SDCC

This allows boards with non-standard sdio cards to fill the CIS/CCCR data.
It is particularly important for old msm72k boards using wl1251.
Also drop the obsolete embedded_sdio_data structure from the header
as it was intended to surve a similiar purpose but was not implemented.

Signed-off-by: Alexander Tarasikov <alexander.tarasikov@gmail.com>
Acked-by: Sahitya Tummala <stummala@codeaurora.org>
[davidb: minor formatting cleanup]
Signed-off-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>