uboot-imx

phy: add a NO-OP phy driver

This driver is used to stub PHY operations in a driver (USB, SATA).
This is useful when the 'client' driver (USB, SATA, ...) uses the PHY
framework and there is no actual PHY harwdare to drive.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>