Introduce a new test, `ipv4_devconf_notify`, to verify that the kernel
sends the appropriate netlink notifications when IPv4 devconf parameters
are modified.
The test depends on the newly introduced iproute2 command:
`ip link set dev <ifname> inet`
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Link: https://patch.msgid.link/20260609204520.4670-3-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>