soc/amd/picasso: move to using smbus_host.h definitions

The SMBus function declarations were duplicated. Use the common
ones provided by smbus_host.h.

Change-Id: Ia8fec8f58d72690d73f2241e69b3ff05f74943a4
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38615
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/picasso/southbridge.c

@@ -29,7 +29,6 @@
 #include <amdblocks/acpi.h>
 #include <soc/cpu.h>
 #include <soc/southbridge.h>
-#include <soc/smbus.h>
 #include <soc/smi.h>
 #include <soc/amd_pci_int_defs.h>
 #include <delay.h>