rule_generator: fix netif NAME= value extraction regex

rule_generator: fix netif NAME= value extraction regex

  $ sed -n -r \
    -e 's/^#.*//' \
    -e 's/[[:space:],]NAME="(eth[0-9]*)"[[:space:]]*(,.*|\\|)$/\1/p' \
    /dev/null /etc/udev/rules.d/70-persistent-net.rules
  SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:16:41:e2:8d:c7", ATTR{type}=="1", KERNEL=="eth*",eth4

  $ sed -n -r \
    -e 's/^#.*//' \
    -e 's/.*[[:space:],]NAME="(eth[0-9]*)".*/\1/p' \
    /dev/null /etc/udev/rules.d/70-persistent-net.rules
  eth4