Use both module name and stem name to filter updatable boot jars

Sometimes the stem property is set to change both the installed file
name and the name use to filter the configured module list, e.g. when
adding a test library to replace the standard library, e.g. test_foo
instead of foo.

Sometimes it is used just to change the installed file name.

This change uses both to filter the updatable boot jars and not just
the stem.

Bug: 180105615
Test: m nothing
Change-Id: I6c459fc3597b1e4f062bc9a4e52843305b538c5f