lib: Remove select of inexistant GENERIC_IO

config option GENERIC_IO was removed but still selected by lib/kconfig
This patch finish the cleaning.

Fixes: 9de8da47 ("kconfig: kill off GENERIC_IO option")
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>