mmc: omap_hsmmc: if multiblock reads are broken, disable them

When device data indicates that multiple block reads are not supported
on a given HSMMC controller instance, log a message to the console, and
pass the appropriate MMC capability flag to the MMC core.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Dave Hylands <dhylands@gmail.com>
Tested-by: Steve Sakoman <sakoman@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>