ARM: OMAP2: Remove legacy USB FS support

ARM: OMAP2: Remove legacy USB FS support

The FS (Full Speed) USB controller is available on 2420 and 2430,
but not being used.

Out of the 2420 based boards only Nokia N8X0 are seeing active
development and they have external HS (High Speed) TUSB controller.
On omap 2430sdp there is MUSB HS controller, so there's no need
to use the legacy USB FS controller.

That leaves only H4 and Apollon boards that could use the FS USB
controller. As both H4 and Apollon boards are old proprietary
development boards, it's unlikely that we have any active
developers working on those boards using the USB.

So remove the FS USB support for omap2 machines. Patches are
welcome if somebody wants to instead fix it all up to the
current standards.

Cc: linux-usb@vger.kernel.org
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>