phy: omap-usb2: Add different compatible for OMAP5

Add a new compatible for OMAP5 since it does not use any of the
OTG operations as of now.
HAS_SRP and SET_VBUS functionalities are used only for OMAP4.

Signed-off-by: George Cherian <george.cherian@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>