ARM: tegra: fix Venice2 SD card VQMMC supply

VDDIO_SDMMC3 is the VQMMC (I/O) supply, not the VMMC (core) supply,
for the SD slot on Venice2.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>