uboot-imx

mxs: Make ehci-mxs multiport capable

Rework ehci-mxs so it supports both ports on MX28. It was necessary
to wrap the per-port configuration into struct ehci_mxs_port and pull
out the clock configuration function.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>