ARM: tegra: apalis-eval: Fix power/wakeup key

Rather than a power key, WAKE1_MICO is actually a standard Apalis MXM3
pin used for wake-up purposes which this patch fixes.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>