Currently, flannel uses an ad-hoc github URL and a version-only tarball
name, even though we already had the github helper (introduced in 2013)
when flannel was introduced (in 2016).
Switch to the github helper, which allows us to get a properly named
tarball.
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Cc: Geoff Levand <geoff@infradead.org>
Acked-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>