ACPI: Clean up some S3 related leftovers

With RELOCATABLE_RAMSTAGE the backing up of low memory
on S3 resume path was dropped. We forgot some things
behind.

Change-Id: I674f23dade0095e64619af0ae81e23368b1ee471
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/42422
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/arch/x86/acpi_s3.c

@@ -6,12 +6,10 @@
 #include <arch/cpu.h>
 #include <cbmem.h>
 #include <commonlib/helpers.h>
+#include <cpu/x86/smm.h>
 #include <fallback.h>
 #include <timestamp.h>
-#include <program_loading.h>
 #include <romstage_handoff.h>
-#include <symbols.h>
-#include <cpu/x86/smm.h>
 
 #if ENV_RAMSTAGE || ENV_POSTCAR