Fix warnings by rustc --print cfg --target ci/switch.json

```
warning: target json file contains unused fields: abi-blacklist, family, has-elf-tls, target-env
```

Author: tesuji

ci/switch.json

@@ -1,30 +1,20 @@
 {
-  "family": "unix",
   "env": "newlib",
-  "target-env": "newlib",
   "target-family": "unix",
   "target-c-int-width": "32",
   "target-endian": "little",
   "target-pointer-width": "64",
   "os": "horizon",
   "arch": "aarch64",
   "panic-strategy": "unwind",
-  "abi-blacklist": [
-      "stdcall",
-      "fastcall",
-      "vectorcall",
-      "thiscall",
-      "win64",
-      "sysv64"
-  ],
   "dynamic-linking" : false,
   "features": "+a53,+strict-align",
   "data-layout": "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128",
   "executables": true,
   "position-independent-executables" : true,
   "linker-flavor": "gcc",
   "llvm-target": "aarch64-unknown-none",
-  "has-elf-tls" : false,
+  "has-thread-local": false,
   "linker-is-gnu" : true,
   "disable-redzone" : true,
   "relocation-model" : "pic",
@@ -34,4 +24,4 @@
   "trap-unreachable" : true,
   "emit-debug-gdb-scripts" : true,
   "requires-uwtable" : true
-}
+}