[BGPVPN] fpm: Build multiarch DEBs (arch <all>)

[BGPVPN] fpm: Build multiarch DEBs (arch <all>)

Update upstream reference to include support for building DEB
packages for architecture <all> instead of the native one, since
apart from one small hardcoded check on Fedora for java version,
most code is arch-independant (python).

TODO:
 Extend check for `uname -m` result for aarch64 and other platforms
 in <networking_odl/devstack/setup_java.sh>.

While at it, make git info variable overrideable, just in case
we want to patch this out of upstream tree locally.

Change-Id: Ia139c8d957f65bb120dca1727fd4a422e2510ea0
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>