um: fix ptrace build error

Both commits 0a3d763f1a68 ("ptrace: cleanup arch_ptrace() on um") and
9b05a69e0534 ("ptrace: change signature of arch_ptrace()") broke the um
build.  This patch fixes the issues.

0a3d763f1a68 introduced the undeclared variable "datavp".  The patch seems
completely untested.  :-(

9b05a69e0534 changed arch_ptrace()'s signature but did not update
um/include/asm/ptrace-generic.h.

Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Jeff Dike <jdike@addtoit.com>
Tested-by: Will Newton <will.newton@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/include/asm/ptrace-generic.h b/arch/um/include/asm/ptrace-generic.h
index 2cd899f..b7c5bab 100644
--- a/arch/um/include/asm/ptrace-generic.h
+++ b/arch/um/include/asm/ptrace-generic.h
@@ -38,8 +38,8 @@
 
 struct task_struct;
 
-extern long subarch_ptrace(struct task_struct *child, long request, long addr,
-			   long data);
+extern long subarch_ptrace(struct task_struct *child, long request,
+	unsigned long addr, unsigned long data);
 extern unsigned long getreg(struct task_struct *child, int regno);
 extern int putreg(struct task_struct *child, int regno, unsigned long value);
 extern int get_fpregs(struct user_i387_struct __user *buf,