fbdev/ep93xx-fb: Output messages with fb_info() and fb_err()

Fix cases were output helpers are called with struct fb_info.dev.
Use fb_info() and fb_err() instead.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-14-tzimmermann@suse.de