Use new static target for libdexfile_support.

This is necessary since the dynamic one is now using dlopen(), which isn't
available in static builds.

Test: m
Test: mmma system/core/{libunwindstack,libbacktrace}, run host gtests (cannot get atest to work)
Bug: 123403798
Bug: 123186083
Change-Id: I06a9cdfe7e7cc01427ffd54b66c8ebab88782260