PTRACE_PEEKDATA consolidation

Identical implementations of PTRACE_PEEKDATA go into generic_ptrace_peekdata()
function.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index eeb1976..477cc8e 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -110,6 +110,7 @@
 		__ptrace_unlink(child);
 }
 
+int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data);
 
 #ifndef force_successful_syscall_return
 /*