arch/x86: Avoid HAVE_SMI_HANDLER conditional with smm-class

Build of the entire smm-class is skipped if we have
HAVE_SMI_HANDLER=n.

Change-Id: I10b4300ddd18b1673c404b45fd9642488ab3186c
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34125
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Lance Zhao <lance.zhao@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/ec/acpi/Makefile.inc

@@ -2,6 +2,6 @@ ifeq ($(CONFIG_EC_ACPI),y)
 
 ramstage-y += ec.c
 romstage-y += ec.c
-smm-$(CONFIG_HAVE_SMI_HANDLER) += ec.c
+smm-y += ec.c
 
 endif

src/ec/lenovo/pmh7/Makefile.inc

@@ -1,7 +1,7 @@
 ifeq ($(CONFIG_EC_LENOVO_PMH7),y)
 
 ramstage-y += pmh7.c
-smm-$(CONFIG_HAVE_SMI_HANDLER) += pmh7.c
+smm-y += pmh7.c
 romstage-y += pmh7.c
 
 endif