By default, don't use a bitness suffix for ART.

This will make it pick up the symlink. Only if the bitness is passed
through the command line will we add it to the path.

Bug: 155861770

Test: dalvik/dx/tests/run-all-tests
Change-Id: I8a26f9f38fa589cad0b1b83041181f7637060861
Merged-In: I8a26f9f38fa589cad0b1b83041181f7637060861
(cherry picked from commit 745e45d44462af1e58a120f4886ea5c307b66a2e)