usb: otg: utils: devres: Add API's to associate a device with the phy

Used devres API's to associate the phy with a device so that on
driver detach, release function is invoked on the devres data(usb_phy)
and devres data(usb_phy) is released.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>