arm64: dts: mediatek: mt8192-asurada: Fix voltage constraint for Vgpu

The MT8192 SoC specifies a maximum voltage for the GPU's digital supply
of 0.88V and the GPU OPPs are declaring a maximum voltage of 0.80V.

In order to keep the GPU voltage in the safe range, change the maximum
voltage for mt6315@7's vbuck1 to 0.80V as sending, for any mistake,
1.193V would be catastrophic.

Fixes: 3183cb62 ("arm64: dts: mediatek: asurada: Add SPMI regulators")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Chen-yu Tsai <wenst@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20230301095523.428461-12-angelogioacchino.delregno@collabora.comSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi

@@ -1408,7 +1408,7 @@ mt6315_7_vbuck1: vbuck1 {
 				regulator-compatible = "vbuck1";
 				regulator-name = "Vgpu";
 				regulator-min-microvolt = <606250>;
-				regulator-max-microvolt = <1193750>;
+				regulator-max-microvolt = <800000>;
 				regulator-enable-ramp-delay = <256>;
 				regulator-allowed-modes = <0 1 2>;
 			};