usb: phy: samsung: remove old common USB PHY code

usb: phy: samsung: remove old common USB PHY code

drivers/usb/phy/phy-samsung-usb[2,3] drivers got replaced by
drivers/phy/phy-samsung-usb[2,3] ones and the old common Samsung
USB PHY code is no longer used.

Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]>
Acked-by: Kyungmin Park <[email protected]>
Reviewed-by: Vivek Gautam <[email protected]>
Reviewed-by: Jingoo Han <[email protected]>
Acked-by: Kishon Vijay Abraham I <[email protected]>
Cc: Kamil Debski <[email protected]>
Signed-off-by: Felipe Balbi <[email protected]>