fbdev/pxa168fb: Do not assign to struct fb_info.dev

Do not assign the hardware device to struct fb_info.dev. The
field references the fbdev software device, which is unrelated.

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/20230613110953.24176-21-tzimmermann@suse.de