x86, dumpstack: Fix unused variable warning

In dump_stack function, bp isn't used anymore, which is introduced by
commit 9c0729d. This patch removes bp
completely.

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: Soeren Sandmann <sandmann@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <AANLkTik9U_Z0WSZ7YjrykER_pBUfPDdgUUmtYx=R74nL@mail.gmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

arch/x86/kernel/dumpstack.c

@@ -197,14 +197,8 @@ void show_stack(struct task_struct *task, unsigned long *sp)
  */
 void dump_stack(void)
 {
-	unsigned long bp = 0;
 	unsigned long stack;
 
-#ifdef CONFIG_FRAME_POINTER
-	if (!bp)
-		get_bp(bp);
-#endif
-
 	printk("Pid: %d, comm: %.20s %s %s %.*s\n",
 		current->pid, current->comm, print_tainted(),
 		init_utsname()->release,