fbdev: don't show logo if driver or fbcon are modular

It was always intended for the logo to be drawn only if both fbcon and the
driver that is mapped to it are both compiled statically.  Currently, if fbcon
is loaded prior to the driver, the logo is not shown.  Reverse the order, and
the code may attempt to draw the logo which is __initdata.  By accident, this
bug is rarely seen because this method of loading the modules is not common
and secondly, a code in fb_prepare_logo() that checks the height of the logo
(now a random value) rarely succeeds.

Fix by drawing the logo only if both fbcon and the driver are statically
compiled.

Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Cc:  Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>