usb: phy: msm: Add host/device devices after registering PHY

hcd/dcd's probe may not find USB2 PHY if their devices are
registered before adding USB PHY. Correct the order in OTG
probe.

Change-Id: I55423a86324dbb35c4bf7c1331594bc16d366217
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>