ARM: OMAP: omap_device: Do not overwrite resources allocated by OF layer

With the new devices (like, AM33XX and OMAP5) we now only support
DT boot mode of operation and now it is the time to start killing
slowly the dependency on hwmod, so with this patch, we are starting
with device resources.
The idea here is implemented considering to both boot modes -
  - DT boot mode
    OF framework will construct the resource structure (currently
    does for MEM & IRQ resource) and we should respect/use these
    resources, killing hwmod dependency.
    If pdev->num_resources > 0, we assume that MEM & IRQ resources
    have been allocated by OF layer already (through DTB).

    Once DMA resource is available from OF layer, we should
    kill filling any resources from hwmod.

  - Non-DT boot mode
    Here, pdev->num_resources = 0, and we should get all the
    resources from hwmod (following existing steps)

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
[b-cousson@ti.com: Fix some checkpatch CHECK issues]
Signed-off-by: Benoit Cousson <b-cousson@ti.com>