So now we can stop to use the efi-stdio as this driver
print on the Framebuffer and the serial at the same time.

This is specially usefull if we want to use the framebuffer via efi-gop for
something else.

Do not forget to disable the efi-stdio device before enabling the console
otherwise you will get double printing.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>