ARM: dts: am33xx: correcting dt node unit address for usb

DT node's unit address should be its own register offset address to make it a
unique across the system. This patch corrects the incorrect USB entries with
correct register offset for unit address.

Cc: stable@vger.kernel.org # v3.12+
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>