udev: use INTERFACE property rather than sysname when processing network interface...

sd-device replaces '!' in sysname with '/', hence sysname may be
different from ifname.
Let's use INTERFACE property when we need network interface name.

This fixes the following unexpected renaming of network interfaces
created with '!' in their name, e.g. 'hoge!foo' -> 'hoge_foo':
```
$ run0 ip link add 'hoge!foo' type dummy
$ ip link show 'hoge!foo'
Device "hoge!foo" does not exist.
$ ip link show 'hoge_foo'
410: hoge_foo: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether ee:54:4a:dd:c4:c7 brd ff:ff:ff:ff:ff:ff
```

Closes #26156.