Revert "network: add "mac" to alternatives name policy by default" (s…

…ystemd#33227)

This reverts commit 0f5a529.

As discussed in systemd#33104,
that patch caused problems in Debian which has a udev drop-in with

  [Match]
  Path=*-usb-*

  [Link]
  NamePolicy=mac

The rename fails:
   eth0: Policy *mac* yields "enx00*".
   eth0: /usr/lib/udev/rules.d/80-net-setup-link.rules:11 NAME 'enx00*'
   eth0: /usr/lib/udev/rules.d/99-systemd.rules:69 RUN '/usr/lib/systemd/systemd-sysctl --prefix=/net/ipv4/conf/$name --prefix=/net/ipv4/neigh/$
   eth0: sd-device: Created database file '/run/udev/data/n9' for '/devices/pci0000:00/0000:00:1c.4/0000:02:00.0/0000:03:01.0/0000:05:00.0/0000:
   eth0: Failed to rename network interface 9 from 'eth0' to 'enx00*': File exists
   eth0: sd-device: Created database file '/run/udev/data/n9' for '/devices/pci0000:00/0000:00:1c.4/0000:02:00.0/0000:03:01.0/0000:05:00.0/0000:
   eth0: Failed to process device, ignoring: File exists

Two network interfaces have the same MAC and it's not marked NET_ADDR_STOLEN.
In this case the conflict is very visible because it causes the rename to fail,
but it would also occur in other cases, for alternative names.

A patch has been submitted for r8152 to properly set NET_ADDR_STOLEN:
https://lore.kernel.org/linux-usb/[email protected]/T/#u

Let's revert this now to avoid a regression. We can try again after the kernel
issue is resolved.

Closes systemd#33104.

network/99-default.link

@@ -11,5 +11,5 @@ OriginalName=*
 
 [Link]
 NamePolicy=keep kernel database onboard slot path
-AlternativeNamesPolicy=database onboard slot path mac
+AlternativeNamesPolicy=database onboard slot path
 MACAddressPolicy=persistent