[PATCH] ppc: fix a bunch of warnings

Building a PowerMac kernel with ARCH=powerpc causes a bunch of warnings,
this fixes some of them

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/include/asm-powerpc/xmon.h b/include/asm-powerpc/xmon.h
index 43f7129..ace2072 100644
--- a/include/asm-powerpc/xmon.h
+++ b/include/asm-powerpc/xmon.h
@@ -7,6 +7,7 @@
 extern int xmon(struct pt_regs *excp);
 extern void xmon_printf(const char *fmt, ...);
 extern void xmon_init(int);
+extern void xmon_map_scc(void);
 
 #endif
 #endif