staging: vt6656: Create new function to set led state.

Create vnt_mac_set_led to set state and led.

state has two modes LEDSTS_TMLEN which sets the blink rate
on TX activity and LEDSTS_STS which sets the led.

As result of this patch ControlvMaskByte becomes dead code.

Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>