Dell Optiplex 980.

Since a few weeks biosdevname fails to name the interface 'em1'. Instead the
onboard network is named 'eno1'. As a result the bridge does not start and the
system is unreachable.

dom0:
root@optiplex:~ # ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group
default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br1
state UP group default qlen 1000
    link/ether b8:ac:6f:a3:7d:0a brd ff:ff:ff:ff:ff:ff
3: enp2s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
qlen 1000
    link/ether 68:05:ca:39:d6:f0 brd ff:ff:ff:ff:ff:ff
4: wlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
qlen 1000
    link/ether 00:23:54:4c:6c:24 brd ff:ff:ff:ff:ff:ff
5: br1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group
default qlen 1000
    link/ether b8:ac:6f:a3:7d:0a brd ff:ff:ff:ff:ff:ff
    inet 172.16.0.3/16 brd 172.16.255.255 scope global br1
       valid_lft forever preferred_lft forever
    inet6 2001:a62:1255:f2ff:1516:bf8d:2253:b820/64 scope global temporary
dynamic
       valid_lft 86304sec preferred_lft 14304sec
    inet6 2001:a62:1255:f2ff:baac:6fff:fea3:7d0a/64 scope global mngtmpaddr
dynamic
       valid_lft 86304sec preferred_lft 14304sec
    inet6 fd00:172:16:0:1516:bf8d:2253:b820/64 scope global temporary dynamic
       valid_lft 86304sec preferred_lft 14304sec
    inet6 fd00:172:16:0:baac:6fff:fea3:7d0a/64 scope global mngtmpaddr dynamic
       valid_lft 86304sec preferred_lft 14304sec
    inet6 fe80::baac:6fff:fea3:7d0a/64 scope link
       valid_lft forever preferred_lft forever

non-dom0:
root@optiplex:~ # ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group
default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: em1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0
state UP group default qlen 1000
    link/ether b8:ac:6f:a3:7d:0a brd ff:ff:ff:ff:ff:ff
3: p4p1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
qlen 1000
    link/ether 68:05:ca:39:d6:f0 brd ff:ff:ff:ff:ff:ff
4: wlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
qlen 1000
    link/ether 00:23:54:4c:6c:24 brd ff:ff:ff:ff:ff:ff
5: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group
default qlen 1000
    link/ether b8:ac:6f:a3:7d:0a brd ff:ff:ff:ff:ff:ff
    inet 172.16.0.3/16 brd 172.16.255.255 scope global br0
       valid_lft forever preferred_lft forever
    inet6 2001:a62:1255:f2ff:a46e:df5c:723:c3ef/64 scope global temporary
dynamic
       valid_lft 86279sec preferred_lft 14279sec
    inet6 2001:a62:1255:f2ff:baac:6fff:fea3:7d0a/64 scope global mngtmpaddr
dynamic
       valid_lft 86279sec preferred_lft 14279sec
    inet6 fd00:172:16:0:a46e:df5c:723:c3ef/64 scope global temporary dynamic
       valid_lft 86279sec preferred_lft 14279sec
    inet6 fd00:172:16:0:baac:6fff:fea3:7d0a/64 scope global mngtmpaddr dynamic
       valid_lft 86279sec preferred_lft 14279sec
    inet6 fe80::baac:6fff:fea3:7d0a/64 scope link
       valid_lft forever preferred_lft forever

(After noticing the error I created a br1 to be able to get back into the
system.)