fix target-pointer-width in tests

Author: WaffleLapkin

tests/x86_64-unknown-kernel.json

@@ -1,7 +1,7 @@
 {
   "llvm-target": "x86_64-unknown-none",
   "target-endian": "little",
-  "target-pointer-width": "64",
+  "target-pointer-width": 64,
   "target-c-int-width": 32,
   "data-layout": "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128",
   "arch": "x86_64",