apalis_imx6: use both sd/mmc interfaces for setsdupdate

During porting to 2016.11 the check of a SD (mmc2) interface
was dropped, this was unintended.

Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Acked-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
1 file changed