arm64: tegra: p2180: Explicitly enable GPU

arm64: tegra: p2180: Explicitly enable GPU

The gpu node originally was explicitly left disabled as it was expected
for the bootloader to enable it. However, this is only done in u-boot.
If u-boot is not in the boot chain, this will never be enabled. Other
Tegra210 devices already explicitly enable the gpu, so make p2180 match.

Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
Link: https://lore.kernel.org/r/20250420-tx1-gpu-v1-1-d500de18e43e@gmail.com
Signed-off-by: Thierry Reding <treding@nvidia.com>