MMC switch command for unsupported feature (e.g. bus width) sets a switch
error bit in card status. This bit should be checked, and, if it's set,
no access with new controller settings should be performed.
Acked-by: Pantelis Antoniou <panto@antoniou-consulting.com>
Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>