Use Image.gz for testing

The output of `make linux_image` is Image.gz, not Image.

Change-Id: I69fe3a56238968096229a27b36602282842ab2f6
1 file changed
tree: 1f0d8e27b94abf6c8d682c6b0a5388602bd2cd19
  1. Makefile
  2. aarch64-unit-tests/