dts: mt7987: drop mt7988 compatible to fix binding error

Author: frank-w

arch/arm64/boot/dts/mediatek/mt7987.dtsi

@@ -487,8 +487,7 @@
 		};
 
 		i2c0: i2c@11003000 {
-			compatible = "mediatek,mt7988-i2c",
-				     "mediatek,mt7981-i2c";
+			compatible = "mediatek,mt7981-i2c";
 			reg = <0 0x11003000 0 0x1000>,
 			<0 0x10217080 0 0x80>;
 			interrupts = <GIC_SPI 136 IRQ_TYPE_LEVEL_HIGH>;