USB: pxa2xx_udc -- cleanups, mostly removing dma hooks

Cleanups to the pxa2xx_udc code:

  - Primarily removing unused DMA hooks.
  - One "sparse" warning removed
  - Remove some Lubbock-only LED hooks (for debugging)

That DMA code was never really completed.  It worked, mostly, for IN
transfers (to the host) if they were fortuitously aligned, but that
code was never fully tested.  And it was never coded for OUT transfers
(which is where DMA would really help) ... because of chip errata on
essentially every chip other than the pxa255, and because of design
botches (nothing automated data toggle).  So it's effectively been
dead code for several years now ... no point in keeping it around.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>