When sending a stop command at the recovery path, use a R1B response
when the failing data request are a WRITE. Thus we also care about the
busy detection completion in this case.

For a failing READ request, we use a R1 response for the stop command,
since we don't need to care about busy detection in this case.

To align behavior between hosts supporting MMC_CAP_WAIT_WHILE_BUSY and
those who are not, we add a CMD13 polling method for the card's status.

We also respect whether the host has specified the max_busy_timeout,
which means we may fallback to CMD13 polling if the timeout is greater
than what the host are able to support.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>