Mario Limonciello's compal-laptop changes were partly based on a reading
of dell-laptop.  Unfortunately dell-laptop set a few bad examples; let's
fix them.

I don't have the hardware to test this, but the first four patches
should be nice and low risk.

dell-laptop: fix a use-after-free error on the failure path
dell-laptop: fix rfkill memory leak on unload and failure paths
dell-laptop: create a platform device as a parent for the rfkill devices
etc.
dell-laptop: add __init to init functions

The last patch adds polling for the hardware switch which blocks all
radios.  This exercises the hardware a little more than before; it would
benefit from testing.  It should be possible to see events generated by
the hardware switch using "udevadm monitor --kernel --environment".

dell-laptop: poll the rfkill hard-block