[POWERPC] 4xx: Create common ppc4xx_reset_system() in ppc4xx_soc.c

This patch creates a common system reset routine for all 40x and 44x
systems. Previously only a 44x routine existed. But since this system
reset via the debug control register is common for 40x and 44x let's
share this code for all those platforms in ppc4xx_soc.c.

This patch also enables CONFIG_4xx_SOC for all 40x and 44x platforms.

Tested on Kilauea (405EX) and Canyonlands (440EX).

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
diff --git a/include/asm-powerpc/ppc4xx.h b/include/asm-powerpc/ppc4xx.h
new file mode 100644
index 0000000..033039a
--- /dev/null
+++ b/include/asm-powerpc/ppc4xx.h
@@ -0,0 +1,18 @@
+/*
+ * PPC4xx Prototypes and definitions
+ *
+ * Copyright 2008 DENX Software Engineering, Stefan Roese <sr@denx.de>
+ *
+ * This 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#ifndef __ASM_POWERPC_PPC4xx_H__
+#define __ASM_POWERPC_PPC4xx_H__
+
+extern void ppc4xx_reset_system(char *cmd);
+
+#endif /* __ASM_POWERPC_PPC4xx_H__ */