Move designware timer OF glue into drivers/clocksource

On Tuesday 10 July 2012, Pavel Machek wrote:

Move dw-apb devicetree bindings code to drivers/clocksource, so it can
be easily shared between picoxcell and socfpga. 

Signed-off-by: Pavel Machek <redacted>

I agree with the patch, but please make it easier to review, either by
using the "-M" flag to git format-patch, or by splitting it into one
patch that holds the changes inside that file and another patch that
moves it.

	Arnd