arch/x86: Obsolete CACHE_AS_RAM config

It was originally inverse of romcc-built romstages on x86,
and is currently always true on x86.

Change-Id: I65fa6b3ce8a86781724bbf08f5eadee4112667c4
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34806
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/cpu/Kconfig

@@ -6,14 +6,9 @@ source "src/cpu/*/Kconfig"
 
 if ARCH_X86
 
-config CACHE_AS_RAM
-	bool
-	default y
-
 config CAR_GLOBAL_MIGRATION
 	bool
 	default n
-	depends on CACHE_AS_RAM
 	help
 	  This option is selected if there is need to migrate CAR globals.
 	  All stages which use CAR globals can directly access the variables

src/cpu/x86/Makefile.inc

@@ -1,8 +1,4 @@
-ifeq ($(CONFIG_ARCH_ROMSTAGE_X86_32)$(CONFIG_ARCH_ROMSTAGE_X86_64),y)
-ifeq ($(CONFIG_CAR_GLOBAL_MIGRATION),y)
-romstage-$(CONFIG_CACHE_AS_RAM) += car.c
-endif
-endif
+romstage-$(CONFIG_CAR_GLOBAL_MIGRATION) += car.c
 
 subdirs-y += pae
 subdirs-$(CONFIG_PARALLEL_MP) += name