usb: add devicetree helpers for determining dr_mode and phy_type

This adds two little devicetree helper functions for determining the
dr_mode (host, peripheral, otg) and phy_type (utmi, ulpi,...) from
the devicetree.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/phy/Makefile b/drivers/usb/phy/Makefile
index a9169cb..070eca3 100644
--- a/drivers/usb/phy/Makefile
+++ b/drivers/usb/phy/Makefile
@@ -5,6 +5,7 @@
 ccflags-$(CONFIG_USB_DEBUG) := -DDEBUG
 
 obj-$(CONFIG_USB_PHY)			+= phy.o
+obj-$(CONFIG_OF)			+= of.o
 
 # transceiver drivers, keep the list sorted