Changes:
- Fix the empty sources.list bug with foreign architectures (Closes: #732255, #773867).
Update setup_apt_sources to look at USE_COMPONENTS if COMPONENTS is empty, so
that some iteration over defined components happens.
- Use debian/changelog timestamp as mtime for devices.tar members (Closes: #774069)
We also remove the timestamp in gzip header. This enables debootstap to be
built reproducibly.
PR: ports/196764
Submitted by: Nikolai Lifanov <lifanov@mail.lifanov.com> (maintainer)