base-files: allow exceptions when removing devicename from LEDs

base-files: allow exceptions when removing devicename from LEDs

Without the model-based devicename for LEDs, there are still cases
where a third component is required, typically when it refers to
internal "devices" like phys etc. An example are the following two
found on ramips:

  - rt2800soc-phy0::radio
  - rt2800pci-phy0::radio

So far, the rt2800*-phy: prefixes would be removed by the devicename
removal ("migration") script, and the configuration for these LEDs
would be broken.

To address this, this patch allows to add arguments to a call of
remove_devicename_leds, which will be compared against the first
part of the LED names/labels, and then be ignored by the routine,
and thus not removed:

  remove_devicename_leds "rt2800soc-phy0" "rt2800pci-phy0"

This mechanism is supposed to be used when a "devicename" applies
to several devices. If only a single device is affected, it might
be more effective to use a case statement and exclude the device
from migration by that entirely.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>