fixed 298ccea from https://gitee.com/zhushengle/kernel_liteos_a/pulls/631

fix: 进程退出前自己回收vmspace中的所有region

背景：
父进程fork一个子进程，调用waitpid等待子进程结束。
子进程dlopen一个文件a.so，并退出。当守护进程正在
1核回收子进程资源时，父进程在0核运行从waitpid返
回后，同时remove a.so概率失败。

Close #I4CKQC

Signed-off-by: zhushengle <zhushengle@huawei.com>
Change-Id: Ie7940e7c931ced10ee357cf9aa7c64355effed49

kernel/base/include/los_vm_map.h

@@ -292,6 +292,8 @@ LosVmSpace *OsCreateUserVmSpace(VOID);
 STATUS_T LOS_VmSpaceClone(LosVmSpace *oldVmSpace, LosVmSpace *newVmSpace);
 LosMux *OsGVmSpaceMuxGet(VOID);
 STATUS_T OsUnMMap(LosVmSpace *space, VADDR_T addr, size_t size);
+STATUS_T OsVmSpaceRegionFree(LosVmSpace *space);
+
 /**
  * thread safety
  * it is used to malloc continuous virtual memory, no sure for continuous physical memory.