Revert "Zero hidl-generated structs (cas)"

This reverts commit 2b537f78527b98c76537ccaa8491d7877cae6305.

Reason for revert: Clearing all hidl_vec/array data instead.

Change-Id: I7d51c5268e1b9020732e34c186e2e452cf044518
diff --git a/cas/1.0/default/MediaCasService.cpp b/cas/1.0/default/MediaCasService.cpp
index b159f5b..dbdd008 100644
--- a/cas/1.0/default/MediaCasService.cpp
+++ b/cas/1.0/default/MediaCasService.cpp
@@ -44,7 +44,7 @@
 
     ALOGV("%s", __FUNCTION__);
 
-    hidl_vec<HidlCasPluginDescriptor> results;
+    vector<HidlCasPluginDescriptor> results;
     mCasLoader.enumeratePlugins(&results);
 
     _hidl_cb(results);