mediacas: make it also work on 64bit only guest

BUG: 178885191

Change-Id: I15d711dee366f7c39d6a89aecf34c9503bf32da8
diff --git a/cas/1.0/default/Android.bp b/cas/1.0/default/Android.bp
index f9977ff..70f4371 100644
--- a/cas/1.0/default/Android.bp
+++ b/cas/1.0/default/Android.bp
@@ -12,7 +12,7 @@
       "TypeConvert.cpp",
     ],
 
-    compile_multilib: "32",
+    compile_multilib: "prefer32",
 
     shared_libs: [
       "android.hardware.cas@1.0",
diff --git a/cas/1.0/default/FactoryLoader.h b/cas/1.0/default/FactoryLoader.h
index 18c2186..45e515a 100644
--- a/cas/1.0/default/FactoryLoader.h
+++ b/cas/1.0/default/FactoryLoader.h
@@ -92,7 +92,12 @@
     }
 
     // no luck, have to search
+#ifdef __LP64__
+    String8 dirPath("/vendor/lib64/mediacas");
+#else
     String8 dirPath("/vendor/lib/mediacas");
+#endif
+
     DIR* pDir = opendir(dirPath.string());
 
     if (pDir == NULL) {
@@ -127,7 +132,12 @@
 
     results->clear();
 
+#ifdef __LP64__
+    String8 dirPath("/vendor/lib64/mediacas");
+#else
     String8 dirPath("/vendor/lib/mediacas");
+#endif
+
     DIR* pDir = opendir(dirPath.string());
 
     if (pDir == NULL) {