sunxi: SATA link timeout fix

After updating u-boot from v2016.01 to 2017.09, issue with
"SATA link 0 timeout." on my Cubietruck board.

mdelay milled after moving satapwr code to board.
"sunxi: Turn satapwr on from board_init"
(sha1: 9fbb0c3a)

After adding the "mdelay(500);"
line that was lost in the path the error is gone.

Signed-off-by: Werner Böllmann <Werner.Boellmann@fh-dortmund.de>
[Rebased and updated change and commit message]
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>