arm64: dts: mediatek: mt8395-genio-1200-evk: Enable GPU

arm64: dts: mediatek: mt8395-genio-1200-evk: Enable GPU

Enable the Mali Valhall GPU on Genio 1200 EVK by providing regulator
supply settingsi to gpu and mfg1, and enable the GPU node.

In addition, set the GPU related regulator voltage range:

1. Set the recommended input voltage range of DVDD_GPU to (0.546V-0.787V),
   based on Table 5-3 of MT8395 Application Processor Datasheet.
   The regulator mt6315_7_vbuck1("Vgpu") connects to the DVDD_GPU input.
   Note that the minimum voltage in SoC eFuse data, which is read by
   MTK-SVS to adjust the regulator voltage, does not go below
   the recommended operating voltage in the datasheet.

2. Set the input voltage of DVDD_SRAM_GPU, supplied by
   mt6359_vsram_others_ldo_reg, to 0.75V, the recommended typical
   operating voltage in MT8395 Application Processor Datasheet.

This patch is tested by enabling CONFIG_DRM_PANFROST and
on Genio 1200 EVK it probed with following dmesg:

```
panfrost 13000000.gpu: clock rate = 700000092
panfrost 13000000.gpu: mali-g57 id 0x9093 major 0x0 minor 0x1 status 0x0
panfrost 13000000.gpu: features: 00000000,000019f7,
					   issues: 00000001,80000400
panfrost 13000000.gpu: Features: L2:0x07120206 Shader:0x00000000
					   Tiler:0x00000809 Mem:0x301
					   MMU:0x00002830 AS:0xff JS:0x7
panfrost 13000000.gpu: shader_present=0x50045 l2_present=0x1
[drm] Initialized panfrost 1.2.0 for 13000000.gpu on minor 0
```

Signed-off-by: Pablo Sun <pablo.sun@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20240912070624.25540-1-pablo.sun@mediatek.com
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>