Use target 'vndk' instead of 'vndk_package' while creating abi references.

Using 'vndk_package' will miss out on vndk libraries not being used by the
lunch target

Bug: 64267858

Test: utils/create_reference_dumps.py

Merged-In: Ifaa61aae715af7f2010aadbfa9864da7c74ca14f
Change-Id: Ifaa61aae715af7f2010aadbfa9864da7c74ca14f
(cherry picked from commit 1ebd366d)