syscalls: make chdir follow path from the current->cwd and return 0 if there's no error

src/tasking/syscalls.c

@@ -445,6 +445,8 @@ int sys_chdir(TrapFrame *tf)
     l9660_dir new_cwd;
     l9660_file placeholder_file;
 
+    new_cwd = *current->cwd;
+
     int status = follow_path((char*)tf->ebx, &placeholder_file, &new_cwd);
 
     if(status == L9660_OK)
@@ -466,6 +468,9 @@ int sys_chdir(TrapFrame *tf)
         case L9660_ENOTDIR:
             return -20;//ENOTDIR
             break;
+        case L9660_OK:
+            return 0;
+            break;
         default:
             return -5;//EIO
             break;