cpu/x86: Declare SMM_ASEG

This is really an inverse of SMM_TSEG to flag
platforms that should potentially move away
from ASEG implementation.

Change-Id: I3b9007c55c75a59a9e6acc0a0e701300f7d21f87
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34134
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/cpu/intel/model_f2x/Kconfig

@@ -6,3 +6,4 @@ config CPU_INTEL_MODEL_F2X
 	select ARCH_RAMSTAGE_X86_32
 	select SMP
 	select SUPPORT_CPU_UCODE_IN_CBFS
+	select SMM_ASEG