device/smbus_host: Declare common early SMBus prototypes

Change-Id: I1157cf391178a27db437d1d08ef5cb9333e976d0
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38233
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/northbridge/intel/i945/raminit.c b/src/northbridge/intel/i945/raminit.c
index c668e79..1c7a1f0 100644
--- a/src/northbridge/intel/i945/raminit.c
+++ b/src/northbridge/intel/i945/raminit.c
@@ -4,6 +4,7 @@
 #include <delay.h>
 #include <device/pci_def.h>
 #include <device/pci_ops.h>
+#include <device/smbus_host.h>
 #include <cf9_reset.h>
 #include <device/mmio.h>
 #include <device/device.h>