Avoid adding VINTF manifest fragment more than once.

In the case of building a multilib library that defines LOCAL_VINTF_FRAGMENTS,
the previous code would create duplicate rules for the fragment. This change
uses the my_vintf_new_installed variable (which may be empty) to avoid the
duplication.

Bug: 139268165
Test: Verify that build warnings are gone, yet VINTF fragment still installed.
Change-Id: I579ec650019a29a6a105118ad5e5ae9376e8d9bc
diff --git a/core/base_rules.mk b/core/base_rules.mk
index 4a0c15b..e3f8a70 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -524,11 +524,11 @@
 
 # Only set up copy rules once, even if another arch variant shares it
 my_vintf_new_pairs := $(filter-out $(ALL_VINTF_MANIFEST_FRAGMENTS_LIST),$(my_vintf_pairs))
-my_vintf_new_installed := $(call copy-many-vintf-manifest-files-checked,$(my_vintf_pairs))
+my_vintf_new_installed := $(call copy-many-vintf-manifest-files-checked,$(my_vintf_new_pairs))
 
 ALL_VINTF_MANIFEST_FRAGMENTS_LIST += $(my_vintf_new_pairs)
 
-$(my_all_targets) : $(my_vintf_installed)
+$(my_all_targets) : $(my_vintf_new_installed)
 endif # LOCAL_VINTF_FRAGMENTS
 endif # !LOCAL_IS_HOST_MODULE
 endif # !LOCAL_UNINSTALLABLE_MODULE