arcfb: use fb_sys_read()

Since arcfb's framebuffer is vmalloc'ed, use the fb_sys_read().

Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 85d0e87..19b7f73 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -420,6 +420,7 @@
 	select FB_SYS_FILLRECT
 	select FB_SYS_COPYAREA
 	select FB_SYS_IMAGEBLIT
+	select FB_SYS_FOPS
 	help
 	  This enables support for the Arc Monochrome LCD board. The board
 	  is based on the KS-108 lcd controller and is typically a matrix