powerpc/ppc/ppc64: Various compile fixes.

This declares powersave_nap in system.h and makes it an int everywhere,
fixes typos for the maple platform, fixes a couple of places where
I missed removing the last two arguments from a message_pass function,
and makes ppc64 consistent with ppc32 in the type of the
pci_bridge.cfg_data field.

Signed-off-by: Paul Mackerras <paulus@samba.org>

include/asm-powerpc/system.h

@@ -180,6 +180,8 @@ extern struct task_struct *_switch(struct thread_struct *prev,
 extern unsigned int rtas_data;
 extern int mem_init_done;	/* set on boot once kmalloc can be called */
 
+extern int powersave_nap;	/* set if nap mode can be used in idle loop */
+
 /*
  * Atomic exchange
  *