OMAP1: DMA: Implement in platform device model

Implement OMAP1 DMA as platform device and add support for
registering through platform device layer using resource
structures.

Signed-off-by: G, Manjunath Kondaiah <manjugk@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>