drm/vboxvideo: Drop CONFIG_VGA_CONSOLE guard to call vgacon_text_force()

It is already handled by the console.h macro since a stub inline function
is defined for vgacon_text_force() if CONFIG_VGA_CONSOLE is not set.

There's no need to have ifdefery in the driver when calling the function.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211112133230.1595307-3-javierm@redhat.com