atmel_usba_udc: Add support for AT91CAP9 UDPHS

This patch is part of the series adding support for the USB High
Speed Device Port on the AT91CAP9 system on chip. The AT91CAP9
uses the same UDPHS IP as the AVR32 and the AT91SAM9RL.

The only differences between the AVR32 and the AT91 version of the
device are in the enable/disable and suspend/wakeup sequences: the
AT91 version needs to toggle the USB bias and pulldown explicitly.

Signed-off-by: Stelian Pop <stelian@popies.net>
Acked-by: Andrew Victor <linux@maxim.org.za>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>