[APPLIED][Maverick][master][SRU][pull-request] Properly initialize UART 4 at Beagleboard-xM

[Stefan Bader]

Waiting for the ARM test build to finish but basically pulled and applied to
master-next in Maverick. I did some administrative changes to the patch headers
(Ricardo, if you could adapt that for the next time that would be awesome).

* Added the BugLink lines to all patches (every patch added to the master
  branch of a released series should have one, it is completely valid to
  have the same bug number/link for several patches that solve one problem).
* Added Ricardo's signed-off-by. This is to document the flow of the patch
  (and also to attribute the work of preparing the set).

Stefan