[CRYPTO] cryptoloop: Select CRYPTO_CBC

As CBC is the default chaining method for cryptoloop, we should select
it from cryptoloop to ease the transition.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/block/Kconfig

@@ -305,6 +305,7 @@ config BLK_DEV_LOOP
 config BLK_DEV_CRYPTOLOOP
 	tristate "Cryptoloop Support"
 	select CRYPTO
+	select CRYPTO_CBC
 	depends on BLK_DEV_LOOP
 	---help---
 	  Say Y here if you want to be able to use the ciphers that are