eudev: modify predictable network if name search

eudev: modify predictable network if name search

Consider a name based on mac address in addition to
those based on slot or path.

Note that as of this commit predictable naming is
suppressed by eudev, but can be enabled by removing
/etc/udev/rules.d/80-net-name-slot.rules from the
root filesystem.

Signed-off-by: Joe Slater <joe.slater@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>