powerpc/85xx: Move mpc85xx_smp_init() decl to a new "smp.h"

This removes a bunch of "extern" declarations and CONFIG_SMP ifdefs.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/platforms/85xx/smp.h

@@ -0,0 +1,15 @@
+#ifndef POWERPC_85XX_SMP_H_
+#define POWERPC_85XX_SMP_H_ 1
+
+#include <linux/init.h>
+
+#ifdef CONFIG_SMP
+void __init mpc85xx_smp_init(void);
+#else
+static inline void mpc85xx_smp_init(void)
+{
+	/* Nothing to do */
+}
+#endif
+
+#endif /* not POWERPC_85XX_SMP_H_ */