reset: Finalize move to new API

Move soft_reset() to `southbridge/amd/common/` it's only used for
amdfam10 now.

Drop hard_reset() for good.

Change-Id: Ifdc5791160653c5578007f6c1b96015efe2b3e1e
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/29059
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/southbridge/amd/amd8111/early_ctrl.c

@@ -15,6 +15,7 @@
 
 #include "amd8111.h"
 #include <reset.h>
+#include <southbridge/amd/common/reset.h>
 
 unsigned get_sbdn(unsigned bus)
 {