New libdnf requires 2.x and is the only consumer in oe-core
(or elsewhere).
(From OE-Core rev: 2c518de672d8876ff96e49b498feb898a497e6a5)
Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>