When the MMC framework was added in u-boot, the mmc_go_idle was
added before mmc_send_op_cond_iter in function mmc_send_op_cond
annotating that some cards seemed to need this. Actually, we still
need to do this in function mmc_complete_op_cond for those cards.
This has been verified on Micron MTFC4GACAECN eMMC chip.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>