soc/intel/skylake: Use common opregion implementation

Enable SOC_INTEL_COMMON_GFX_OPREGION for all FSP versions.
Allows to get rid of opregion.c, as it's no longer needed.

Change-Id: I39190488e12917a09dbf7ee3947a33940ebc290b
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/20222
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
diff --git a/src/soc/intel/skylake/Kconfig b/src/soc/intel/skylake/Kconfig
index af1381a..32c2654 100644
--- a/src/soc/intel/skylake/Kconfig
+++ b/src/soc/intel/skylake/Kconfig
@@ -83,6 +83,7 @@
 	select UDELAY_TSC
 	select ACPI_NHLT
 	select HAVE_FSP_GOP
+	select SOC_INTEL_COMMON_GFX_OPREGION
 
 config MAINBOARD_USES_FSP2_0
 	bool
@@ -93,7 +94,6 @@
 	depends on MAINBOARD_USES_FSP2_0
 	select PLATFORM_USES_FSP2_0
 	select ADD_VBT_DATA_FILE if RUN_FSP_GOP
-	select SOC_INTEL_COMMON_GFX_OPREGION
 	select POSTCAR_CONSOLE
 	select POSTCAR_STAGE