arm64: dts: mt8183: refine gamma compatible name

mt8183 gamma is different with mt8173
remove mt8173 compatible name for mt8183 gamma

Fixes: 91f9c963 ("arm64: dts: mt8183: Add display nodes for MT8183")
Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20210128112314.1304160-3-hsinyi@chromium.orgSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt8183.dtsi

@@ -1055,8 +1055,7 @@ aal0: aal@14010000 {
 		};
 
 		gamma0: gamma@14011000 {
-			compatible = "mediatek,mt8183-disp-gamma",
-				     "mediatek,mt8173-disp-gamma";
+			compatible = "mediatek,mt8183-disp-gamma";
 			reg = <0 0x14011000 0 0x1000>;
 			interrupts = <GIC_SPI 234 IRQ_TYPE_LEVEL_LOW>;
 			power-domains = <&spm MT8183_POWER_DOMAIN_DISP>;