ARC: Fix KSTK_ESP()

/proc/<pid>/maps currently don't annotate stack vma with "[stack]"
This is because KSTK_ESP ie expected to return usermode SP of tsk while
currently it returns the kernel mode SP of a sleeping tsk.

While the fix is trivial, we also need to adjust the ARC kernel stack
unwinder to not use KSTK_SP and friends any more.

Cc: <stable@vger.kernel.org>
Reported-and-suggested-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c
index 6492507..92320d6 100644
--- a/arch/arc/kernel/stacktrace.c
+++ b/arch/arc/kernel/stacktrace.c
@@ -73,9 +73,9 @@
 
 		frame_info->task = tsk;
 
-		frame_info->regs.r27 = KSTK_FP(tsk);
-		frame_info->regs.r28 = KSTK_ESP(tsk);
-		frame_info->regs.r31 = KSTK_BLINK(tsk);
+		frame_info->regs.r27 = TSK_K_FP(tsk);
+		frame_info->regs.r28 = TSK_K_ESP(tsk);
+		frame_info->regs.r31 = TSK_K_BLINK(tsk);
 		frame_info->regs.r63 = (unsigned int)__switch_to;
 
 		/* In the prologue of __switch_to, first FP is saved on stack