USDHC tuning circuit should be reset before every time card enumeration
or re-enumeration.

SD3.0 card need tuning. For SDR104 card, when system suspend in standby
mode, and then resume back, the IO timing is still SDR104(tuned) which
may result in card re-enumeration fail in low card speed(400khz) for some
cards. And we did meet the issue that in certain probability, SDR104
card meet mmc command CRC/Timeout error when send CMD2 during mmc bus
resume.

This patch reset the tuning circuit when the ios timing is
MMC_TIMING_LEGACY/MMC_TIMING_MMC_HS/MMC_TIMING_SD_HS, which means both
mmc_power_up() and mmc_power_off() will reset the tuning circuit.
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Acked-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>