sh: Proper show_stack/show_trace() implementation.

This splits out some of the previous show_stack() implementation which
was mostly doing the show_trace() work without actually dumping any of
the stack contents. This now gets split in to two sections, where we
do the fetching of the stack pointer and subsequent stack dumping in
show_stack(), while moving the call trace in to show_trace().

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh/processor.h b/include/asm-sh/processor.h
index 4747738..45bb74e 100644
--- a/include/asm-sh/processor.h
+++ b/include/asm-sh/processor.h
@@ -255,6 +255,8 @@
  */
 #define thread_saved_pc(tsk)	(tsk->thread.pc)
 
+void show_trace(struct task_struct *tsk, unsigned long *sp,
+		struct pt_regs *regs);
 extern unsigned long get_wchan(struct task_struct *p);
 
 #define KSTK_EIP(tsk)  ((tsk)->thread.pc)