[Add] add xv6-rv

lasoft/xv6-la/kernel/stat.h

@@ -0,0 +1,11 @@
+#define T_DIR     1   // Directory
+#define T_FILE    2   // File
+#define T_DEVICE  3   // Device
+
+struct stat {
+  int dev;     // File system's disk device
+  uint ino;    // Inode number
+  short type;  // Type of file
+  short nlink; // Number of links to file
+  uint64 size; // Size of file in bytes
+};