AGESA: Introduce AGESA_LEGACY and its counterpart

We define AGESA_LEGACY as an implementation of mainboard
that has its romstage main completely under mainboard/
directory. We have learnt from other platforms this approach
has several downsides when it comes to making platform-wide
improvements.

We start by creating per-family romstage.c file, which
boards will gradually take into use by removing the
AGESA_LEGACY Kconfig option we here apply to all of them.

Change-Id: Id01931e185a023039a60af16a678de9966db8d65
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/18619
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc@marcjonesconsulting.com>
Reviewed-by: Martin Roth <martinroth@google.com>
diff --git a/src/northbridge/amd/agesa/state_machine.h b/src/northbridge/amd/agesa/state_machine.h
new file mode 100644
index 0000000..f34fd0e
--- /dev/null
+++ b/src/northbridge/amd/agesa/state_machine.h
@@ -0,0 +1,28 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2016 Kyösti Mälkki
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _STATE_MACHINE_H_
+#define _STATE_MACHINE_H_
+
+#include <stdint.h>
+
+struct sysinfo
+{
+	int s3resume;
+};
+
+void board_BeforeAgesa(struct sysinfo *cb);
+
+#endif /* _STATE_MACHINE_H_ */