Add test for elf-hash and packed relocations

This adds CTS test for system libraries to support
workaround for http://b/24465209: some apps require
a subset of system libs to have elf-hash and not to
use packed relocations.

Bug: http://b/32917341
Bug: http://b/24465209
Test: bionic-unit-tests --gtest_filter=Dl*:dl*
Change-Id: Ia0bc28506b1f1f97d4cf902d73b0769e2815fed3