Install VNDK_USING_CORE_VARIANT_LIBRARIES

With TARGET_VNDK_USE_CORE_VARIANT := true, some VNDK libraries are not
installed and instead system variants are used at runtime.

When building system only, VNDK_USING_CORE_VARIANT_LIBRARIES are not
installed under /system because there is no dependency to trigger
installing. (By definition, /vendor modules depends on vndk libs)

Bug: 148803529
Test: lunch aosp_cf_x86_go_phone-userdebug
      m systemimage # should install vndk libraries of core variant

Change-Id: Ied4347969955491b13dc674f2e8453d76592d1d7
diff --git a/target/product/gsi/Android.mk b/target/product/gsi/Android.mk
index 4f2027f..bd8450b 100644
--- a/target/product/gsi/Android.mk
+++ b/target/product/gsi/Android.mk
@@ -163,6 +163,7 @@
     vndkcorevariant.libraries.txt \
     $(addsuffix .vendor,$(VNDK_CORE_LIBRARIES)) \
     $(addsuffix .vendor,$(VNDK_SAMEPROCESS_LIBRARIES)) \
+    $(VNDK_USING_CORE_VARIANT_LIBRARIES) \
     com.android.vndk.current
 endif
 include $(BUILD_PHONY_PACKAGE)