w1: select crc16 library for ds2406

commit 94859308a2 "w1: new w1_ds2406 driver" added a new driver
that uses the crc16 library, but didn't ensure that the core is
there. This adds the necessary Kconfig statements, just like we
have it for other w1 drivers.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Scott Alfter <scott@alfter.us>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/w1/slaves/Kconfig

@@ -40,6 +40,7 @@ config W1_SLAVE_DS2413
 
 config W1_SLAVE_DS2406
 	tristate "Dual Channel Addressable Switch 0x12 family support (DS2406)"
+	select CRC16
 	help
 	  Say Y or M here if you want to use a 1-wire
 	  DS2406 Dual Channel Addressable Switch.  EPROM read/write