使用DragonReach启动shell，修改getdents (#391)

* 使用DragonReach启动shell，修改getdents

* 更改关闭pipe时断言报错问题，以及DragonReach启动shell阶段版本

* 修改目录结构

* update

* 解决小问题

* 调整dragon reach版本号

* 设置make clean的时候不清空应用程序的缓存。
指定relibc版本号

---------

Co-authored-by: longjin <longjin@RinGoTek.cn>

user/dadk/target/x86_64-unknown-dragonos.json

@@ -0,0 +1,35 @@
+{
+    "arch": "x86_64",
+    "code-model": "kernel",
+    "cpu": "x86-64",
+    "os": "dragonos",
+    "target-endian": "little",
+    "target-pointer-width": "64",
+    "target-family": [
+        "unix"
+    ],
+    "env": "musl",
+    "target-c-int-width": "32",
+    "data-layout": "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128",
+    "disable-redzone": true,
+    "features": "-3dnow,-3dnowa,-avx,-avx2",
+    "linker": "rust-lld",
+    "linker-flavor": "ld.lld",
+    "llvm-target": "x86_64-unknown-none",
+    "max-atomic-width": 64,
+    "panic-strategy": "abort",
+    "position-independent-executables": true,
+    "relro-level": "full",
+    "stack-probes": {
+        "kind": "inline-or-call",
+        "min-llvm-version-for-inline": [
+            16,
+            0,
+            0
+        ]
+    },
+    "static-position-independent-executables": true,
+    "supported-sanitizers": [
+        "kcfi"
+    ]
+}