mb/kontron/bsl6: Fix overridden hwmon settings

Add missing device nodes as the `chip` entry needs one to actually
get hooked up.

Change-Id: If34f4919a5499b3148c7e4408cc753fbd909693a
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57467
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Maxim Polyakov <max.senia.poliak@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/kontron/bsl6/variants/boxer26/overridetree.cb

@@ -45,6 +45,8 @@ chip soc/intel/skylake
 			chip drivers/i2c/nct7802y
 				register "fan[1].mode" = "FAN_MANUAL"
 				register "fan[1].duty_cycle" = "100"
+
+				device i2c 0x2e on end
 			end
 		end # SMBus
 		device pci 1f.5 on  end # PCH SPI

src/mainboard/kontron/bsl6/variants/bsl6/overridetree.cb

@@ -37,6 +37,8 @@ chip soc/intel/skylake
 								     { 50, 60 },
 								     { 60, 76 } }"
 				register "fan[1].smart.critical_temp" = "80"
+
+				device i2c 0x2e on end
 			end
 		end # SMBus
 	end