Use the global default cpp_std.

Bug: http://b/344590580
Change-Id: I7637aaead9c61a396bf01f5cc7d704c911c77e41
diff --git a/Android.bp b/Android.bp
index 6a0d6ff..99be594 100644
--- a/Android.bp
+++ b/Android.bp
@@ -65,7 +65,6 @@
         "-Woverloaded-virtual",
         "-DVK_EXPORT= ",
     ],
-    cpp_std: "c++17",
 
     arch: {
         x86: {