mmc: tmio: reset the controller after power-up

mmc: tmio: reset the controller after power-up

This fixes two reported problems:
1. after a system resume the controller isn't functioning until a command
   runs on a timeout and a controller reset is performed.
2. if a card is ejected during a running write operation, its re-insertion
   isn't detected.

Reported-by: Nguyen Viet Dung <nv-dung@jinso.co.jp>
Reported-by: Nguyen Hong Ky <nh-ky@jinso.co.jp>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Tested-by: Nguyen Viet Dung <nv-dung@jinso.co.jp>
Tested-by: Nguyen Hong Ky <nh-ky@jinso.co.jp>
Signed-off-by: Chris Ball <cjb@laptop.org>