Disintegrate asm/system.h for PowerPC

Disintegrate asm/system.h for PowerPC.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cc: linuxppc-dev@lists.ozlabs.org
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 5b43325..8d8e028 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -36,7 +36,7 @@
 #include <asm/uaccess.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>
-#include <asm/system.h>
+#include <asm/switch_to.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/syscalls.h>