ARM: tegra: add SD wp-gpios to Venice2 DT

Venice2 can detect write-protect on the SD card. Add the required
DT entries to allow this.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
[swarren: fixed GPIO polarity per Thierry's testing]
Tested-by: Thierry Reding <treding@nvidia.com>

diff --cc arch/arm/boot/dts/tegra124-venice2.dts
Simple merge