Correct type of appData field

bug: 77732157

test: CTS MediaCasTest; VTS VtsHalCasV1_0Target.
Change-Id: I18b4e9afb52fee72d55b13a48ac1339cf4728983
diff --git a/cas/1.0/default/MediaCasService.cpp b/cas/1.0/default/MediaCasService.cpp
index ca43224..dbdd008 100644
--- a/cas/1.0/default/MediaCasService.cpp
+++ b/cas/1.0/default/MediaCasService.cpp
@@ -69,7 +69,7 @@
     if (mCasLoader.findFactoryForScheme(CA_system_id, &library, &factory)) {
         CasPlugin *plugin = NULL;
         sp<CasImpl> casImpl = new CasImpl(listener);
-        if (factory->createPlugin(CA_system_id, (uint64_t)casImpl.get(),
+        if (factory->createPlugin(CA_system_id, casImpl.get(),
                 &CasImpl::OnEvent, &plugin) == OK && plugin != NULL) {
             casImpl->init(library, plugin);
             result = casImpl;