Commit 8f24ee6382 ("uqmi: Add proper IPv6 support") changed the code
to fetch the IPv4 address via QMI by default instead of using DHCP to
make it consistent with the IPv6 codepath.
This breaks on at least some Sierra Wireless cards, where data exchanges
fail to work until the host has fetched a DHCP lease.
Leave v6 as it is, but always use DHCP for v4.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
3b9b963e6e