Add "apex_vndk" module type

"apex_vndk" is a variant of "apex" module.

apex_vndk {
  name: "com.android.vndk",
  ..
}

This rule is used to produce a VNDK APEX per vndk version.
It supports automatic inclusion of vndk libs.

If "vndk_version" property is set, the prebuilt vndk libs of
the version will be included in the apex bundle.

apex_vndk {
  name: "com.android.vndk.v29"
  vndk_version: "29",
  ...
}

Otherwise, platform's vndk version is used.

This will replace /system/{lib}/vndk-{ver} and vndk-sp-{ver}.

Bug: 134357236
Bug: 139772411
Test: m com.android.vndk
Change-Id: Ib5c86e625839389670d13c683a7427198ef6852f
diff --git a/cc/vndk_prebuilt.go b/cc/vndk_prebuilt.go
index c8ff87f..1dfe8ea 100644
--- a/cc/vndk_prebuilt.go
+++ b/cc/vndk_prebuilt.go
@@ -202,11 +202,11 @@
 //            },
 //        },
 //    }
-func vndkPrebuiltSharedFactory() android.Module {
+func VndkPrebuiltSharedFactory() android.Module {
 	module := vndkPrebuiltSharedLibrary()
 	return module.Init()
 }
 
 func init() {
-	android.RegisterModuleType("vndk_prebuilt_shared", vndkPrebuiltSharedFactory)
+	android.RegisterModuleType("vndk_prebuilt_shared", VndkPrebuiltSharedFactory)
 }