[IMX8MM][MYON2][VIDEO] adv7535: fix init sequence

There is a problem with the default NXP driver for ADV7535 on the Myon2 iMX8MM board
(no HDMI signal on a display). But HDMI works well with the init sequence from the uboot-imx-kuk
https://git.seco.com/seco-ne/3rd-party/kuk/uboot-imx-kuk/-/blob/d795323705d15c6e9be8326af80d441d10fdc3e9/board/keithkoep/trizeps8mini/display.c#L227

After bisecting the changes, it turns out that only value for one register
should be adjusted, to make HDMI work again.

drivers/video/adv7535.c

@@ -86,7 +86,11 @@ static int adv7535_enable(struct udevice *dev)
 	adv7535_i2c_reg_write(dev, 0x9A, 0xff, 0xE0);
 	adv7535_i2c_reg_write(dev, 0xBA, 0xff, 0x70);
 	adv7535_i2c_reg_write(dev, 0xDE, 0xff, 0x82);
+#if defined(CONFIG_TARGET_SECO_IMX8MM_MYON2)
+	adv7535_i2c_reg_write(dev, 0xE4, 0xff, 0xC0);
+#else
 	adv7535_i2c_reg_write(dev, 0xE4, 0xff, 0x40);
+#endif
 	adv7535_i2c_reg_write(dev, 0xE5, 0xff, 0x80);
 	adv7535_i2c_reg_write(priv->cec_dev, 0x15, 0xff, 0xD0);
 	adv7535_i2c_reg_write(priv->cec_dev, 0x17, 0xff, 0xD0);