video: fix bug in cfb_console.c code

Fix bug in drawing long version/info strings:
U-Boot version string like
"U-Boot 2009.03-05647-g7c51e06 (Apr 23 2009 - 12:40:00) MPC83XX"
is long and doesn't wrap around correctly while drawing
beside the logo. Such long strings partially overwrite
the logo. This patch is an attempt to fix it.

Signed-off-by: Anatolij Gustschin <agust@denx.de>