powerpc: merge idle_power4.S and trapc.s

Use idle_power4.S from ppc64 as we are not going to support
32 bit power4 in the merged tree.

Merge ppc64 traps.c into powerpc traps.c:
	use ppc64 versions of exception routine names
		(as they don't have StudlyCaps)
	make all the versions if die() have the same
		prototype

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
diff --git a/include/asm-ppc/system.h b/include/asm-ppc/system.h
index d754ab5..6a49b13 100644
--- a/include/asm-ppc/system.h
+++ b/include/asm-ppc/system.h
@@ -87,7 +87,7 @@
 extern void *cacheable_memcpy(void *, const void *, unsigned int);
 extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);
 extern void bad_page_fault(struct pt_regs *, unsigned long, int);
-extern void die(const char *, struct pt_regs *, long);
+extern int die(const char *, struct pt_regs *, long);
 extern void _exception(int, struct pt_regs *, int, unsigned long);
 #ifdef CONFIG_BOOKE_WDT
 extern u32 booke_wdt_enabled;