soc/intel: Drop spurious includes

Change-Id: I2fff107e38abdd34f2d80d4d258be4c429d371e7
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34868
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/soc/intel/cannonlake/memmap.c

@@ -24,7 +24,6 @@
 #include <intelblocks/ebda.h>
 #include <intelblocks/systemagent.h>
 #include <soc/pci_devs.h>
-#include <soc/smm.h>
 #include <soc/systemagent.h>
 #include <stdlib.h>