fbdev: do not let CONFIG_FB_DEFERRED_IO default to y

CONFIG_FB_DEFERRED_IO can not be turned off, while it's already selected
automatically by the drivers that need it.

Although it's nice to have more compile-coverage, not being able to disable a
rarely used feature is annoying.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NJaya Kumar <jayakumar.lkml@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/video/Kconfig

@@ -171,7 +171,6 @@ config FB_SYS_FOPS
 config FB_DEFERRED_IO
 	bool
 	depends on FB
-	default y
 
 config FB_METRONOME
 	tristate