fbdev: atafb: Stop printing virtual screen_base

Printing (hashed) virtual addresses is useless.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>