team: reset team's flags when down link is P2P device

team: reset team's flags when down link is P2P device

When adding a point to point downlink to team device, we neglected to reset
the team's flags, which were still using flags like BROADCAST and
MULTICAST. Consequently, this would initiate ARP/DAD for P2P downlink
interfaces, such as when adding a GRE device to team device. Fix this by
remove multicast/broadcast flags and add p2p and noarp flags.

After removing the none ethernet interface and adding an ethernet interface
to team, we need to reset team interface flags. Unlike bonding interface,
team do not need restore IFF_MASTER, IFF_SLAVE flags.

Reported-by: Liang Li <liali@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2221438
Fixes: 1d76efe1577b ("team: add support for non-ethernet devices")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>