ARM: tegra: ouya: Fix eMMC on specific bootloaders

Ouya fails to detect the eMMC module when booted via certain bootloaders.
Fastboot and hard-kexec bootloaders fail while u-boot does not. It was
discovered that the issue manifests if the sdmmc4 alternate configuration
clock pin is input disabled.

Ouya uses sdmmc4 in the primary pin configuration. It is unknown why this
occurs, though it is likely related to other eMMC limitations experienced
on Ouya.

For now, fix it by enabling input on cam_mclk_pcc0.

Fixes: d7195ac5 ("ARM: tegra: Add device-tree for Ouya")
Reported-by: Matt Merhar <mattmerhar@protonmail.com>
Tested-by: Matt Merhar <mattmerhar@protonmail.com>
Signed-off-by: Peter Geis <pgwipeout@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>