Fix dexlayout fixed point test

Previously, the dex location did not match the one in the profile.
This caused the second dexlayout to not match the checksum and not
use the profile.

Also added a generic function to generate a profile based on an input
dex.

Test: test-art-host

Bug: 62040831

Change-Id: I2b4fb383ec7a46b158f763de13ecbcd8a8c6180d