Replace dl_hook with "src_path" and "src_files"
Test Plan:
Pass: successfully build stx-openstack-helm
Pass: No difference comparing with the result of dl_hook
Story: 2009101
Task: 43801
Signed-off-by: Yue Tao <Yue.Tao@windriver.com>
Change-Id: I477c0b51ed735f9bcab6bf80e96a109f24c96710