lava_dispatcher: fix path in the compressed overlay

When CompressOverlay action runs it strips all the directories before "lava-XXXX" even if lava_test_results_dir variable is changed in the context. After that most of the classes apply overlay to "/" path in the selected partition. This causes mismatch between path expected in the test shell scripts and the actual path.

This patch uses lava_test_results_dir variable directly in the archive creation which fixes the issue.

Signed-off-by: Milosz Wasilewski milosz.wasilewski@oss.qualcomm.com