mmc: core: for data errors, take response of stop cmd into account

Some errors are flagged only with the next command after a multiblock
transfer, e.g. ECC error. So, when checking for data transfer errors,
we check the result from the stop command as well.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>