powerpc: Unify the 32 and 64 bit idle loops

This unifies the 32-bit (ARCH=ppc and ARCH=powerpc) and 64-bit idle
loops.  It brings over the concept of having a ppc_md.power_save
function from 32-bit to ARCH=powerpc, which lets us get rid of
native_idle().  With this we will also be able to simplify the idle
handling for pSeries and cell.

Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/include/asm-powerpc/reg.h b/include/asm-powerpc/reg.h
index 72bfe3a..bd467bf 100644
--- a/include/asm-powerpc/reg.h
+++ b/include/asm-powerpc/reg.h
@@ -622,6 +622,10 @@
 extern unsigned long scom970_read(unsigned int address);
 extern void scom970_write(unsigned int address, unsigned long value);
 
+#else
+#define ppc64_runlatch_on()
+#define ppc64_runlatch_off()
+
 #endif /* CONFIG_PPC64 */
 
 #define __get_SP()	({unsigned long sp; \