linux-phytec-fsl

mmc: sdhci: execute tuning when device is not busy

We find tuning timeout because of the secure erase operation lasts too
long, so don't do tuning when device is busy.

Signed-off-by: Yi Sun <yi.y.sun@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>