target.json: Update data-layout

This makes us match LLVM's default for x86_64, and prevents a warning.

Signed-off-by: Joe Richey <joerichey@google.com>

Author: josephlr

target.json

@@ -1,6 +1,6 @@
 {
   "llvm-target": "x86_64-unknown-none",
-  "data-layout": "e-m:e-i64:64-f80:128-n8:16:32:64-S128",
+  "data-layout": "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128",
   "arch": "x86_64",
   "target-endian": "little",
   "target-pointer-width": "64",