mvebu: a37xx: Add init for ESPRESSBin Topaz switch

mvebu: a37xx: Add init for ESPRESSBin Topaz switch

Implement the board-specific network init function for
ESPRESSOBin community board, setting the on-board Topaz
switch port to forward mode and allow network connection
through any of the available Etherenet ports.

Signed-off-by: Konstantin Porotchkin <[email protected]>
Cc: Stefan Roese <[email protected]>
Cc: Igal Liberman <[email protected]>
Cc: Nadav Haklai <[email protected]>
Cc: Joe Hershberger <[email protected]>
Reviewed-by: Joe Hershberger <[email protected]>
Signed-off-by: Stefan Roese <[email protected]>