video: Name consoles by their number

We must use the console name in the 'stdout' variable to select the one
we want. At present the name is formed from the driver name with a suffix
indicating the rotation value.

It seems better to name them sequentially since this can be controlled by
driver order. So adjust the code to use 'vidconsole' for the first,
'vidconsole1' for the second, etc.

Signed-off-by: Simon Glass <sjg@chromium.org>