drivers:usb:common:fsl-dt-fixup: Move device-tree fixup framework to common file

Move usb device-tree fixup framework from ehci-fsl.c to common place so
that it can be used by other drivers as well (xhci-fsl.c).

Signed-off-by: Ramneek Mehresh <ramneek.mehresh@nxp.com>
Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
Acked-by: Marek Vasut <marex@denx.de>