Fix sshtestagent to return exit status correctly.
Also return true for vsg health if vsg doesn't have an ip configured.

Change-Id: Ie4dea9a5efa629a23834438fd86ab15460c94e6c
diff --git a/src/test/utils/VSGAccess.py b/src/test/utils/VSGAccess.py
index cb47805..392ebde 100644
--- a/src/test/utils/VSGAccess.py
+++ b/src/test/utils/VSGAccess.py
@@ -317,7 +317,7 @@
 
     def get_health(self):
         if self.ip is None:
-            return False
+            return True
         cmd = 'ping -c 1 {}'.format(self.ip)
         st, _ = self.run_cmd_compute(cmd)
         return st