fbdev: pass struct fb_info to fb_read and fb_write

It is unnecessary to pass struct file to fb_read() and fb_write() in struct
fb_ops. For consistency with the other methods, pass struct fb_info instead.

Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>