lemp9: Remove backlight code

src/mainboard/system76/lemp9/acpi/backlight.asl

@@ -1,27 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/* This file is part of the coreboot project. */
-
-Scope (GFX0)
-{
-	Name (BRIG, Package (0x12)
-	{
-		100, /* default AC */
-		100, /* default Battery */
-		  6,
-		 12,
-		 19,
-		 25,
-		 31,
-		 38,
-		 44,
-		 50,
-		 56,
-		 62,
-		 69,
-		 75,
-		 81,
-		 88,
-		 94,
-		100,
-	})
-}

src/mainboard/system76/lemp9/acpi/ec.asl

@@ -116,8 +116,6 @@ Device (EC0)
 		Debug = "EC: Brightness Down"
 		if (^^^^HIDD.HRDY) {
 			^^^^HIDD.HPEM (20)
-		} Else {
-			\_SB.PCI0.GFX0.DECB ()
 		}
 	}
 
@@ -126,8 +124,6 @@ Device (EC0)
 		Debug = "EC: Brightness Up"
 		if (^^^^HIDD.HRDY) {
 			^^^^HIDD.HPEM (19)
-		} Else {
-			\_SB.PCI0.GFX0.INCB ()
 		}
 	}
 

src/mainboard/system76/lemp9/devicetree.cb

@@ -169,10 +169,6 @@ chip soc/intel/cannonlake
 	# Serial IRQ Continuous
 	register "serirq_mode" = "SERIRQ_CONTINUOUS"
 
-# Graphics (soc/intel/cannonlake/graphics.c)
-	# IGD Displays
-	register "gfx" = "GMA_STATIC_DISPLAYS(0)"
-
 # LPC (soc/intel/cannonlake/lpc.c)
 	# LPC configuration from lspci -s 1f.0 -xxx
 	# Address 0x84: Decode 0x80 - 0x8F (Port 80)