NET: Add Vitesse VSC7385 firmware uploading

The Vitesse VSC7385 is a 5-port switch found on the Freescale MPC8349E-mITX
and other boards.  A small firwmare must be uploaded to its on-board memory
before it can be enabled.  This patch adds the code which uploads firmware
(but not the firmware itself).

Previously, this feature was provided by a U-Boot application that was
made available only on Freescale BSPs.  The VSC7385 firmware must still
be obtained separately, but at least there is no longer a need for a separate
application.

Signed-off-by: Timur Tabi <timur@freescale.com>
Acked-by: Ben Warren <biggerbadderben@gmail.com>