Description:[feature] support flush hievent interface

Change-Id: I228c8e8845e175b53f2c8b9f77dc64ec1d3a26a9
Signed-off-by: Nshenchenkai <shenchenkai@huawei.com>

hievent/include/hiview_hievent.h

@@ -57,5 +57,6 @@ int HiviewHieventSetTime(struct HiviewHievent *event, long long seconds);
 int HiviewHieventAddFilePath(struct HiviewHievent *event, const char *path);
 int HiviewHieventReport(struct HiviewHievent *obj);
 void HiviewHieventDestroy(struct HiviewHievent *event);
+void HiviewHieventFlush(void);
 
 #endif /* HIVIEW_HIEVENT_H */

hievent/src/hiview_hievent.c

@@ -543,3 +543,11 @@ void HiviewHieventDestroy(struct HiviewHievent *event)
     }
     LOS_MemFree((VOID *)OS_SYS_MEM_ADDR, event);
 }
+
+void HiviewHieventFlush(void)
+{
+    // magic number 0x7BBE69BD for notify hiview to flush hievent file
+    struct HiviewHievent *hievent = HiviewHieventCreate(0x7BBE69BD);
+    HiviewHieventReport(hievent);
+    HiviewHieventDestroy(hievent);
+}