um/x86: merge (and trim) 32- and 64-bit variants of ptrace.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/x86/um/tls_32.c b/arch/x86/um/tls_32.c
index c6c7131..baba84f 100644
--- a/arch/x86/um/tls_32.c
+++ b/arch/x86/um/tls_32.c
@@ -219,7 +219,7 @@
 	int idx, ret = -EFAULT;
 
 	if (copy_from_user(&info,
-			   (void __user *) UPT_ESI(&new->thread.regs.regs),
+			   (void __user *) UPT_SI(&new->thread.regs.regs),
 			   sizeof(info)))
 		goto out;