nvmem: NVMEM_NINTENDO_OTP should depend on WII

The Nintendo Wii and Wii U OTP is only present on Nintendo Wii and Wii U
consoles.  Hence add a dependency on WII, to prevent asking the user
about this driver when configuring a kernel without Nintendo Wii and Wii
U console support.

Fixes: 3683b761

 ("nvmem: nintendo-otp: Add new driver for the Wii and Wii U OTP")
Reviewed-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/01318920709dddc4d85fe895e2083ca0eee234d8.1631611652.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>