USB: device DMA support on OMAP2

The current omap udc dosen't support the DMA mode and it has some problem
at setup time on OMAP2 with previous patch file.  I found that the code
assumes bulk out required the big data transfer.  But MODE SELECT(6) sent
the only 24 bytes.  it makes a problem.  So I implement the small packets
handling for it.

It is tested with both linux and windows.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>