crypto: arc4 - now arc needs blockcipher support

Since commit ce6dd368 ("crypto: arc4 - improve performance by adding
ecb(arc4)) we need to pull in a blkcipher.

|ERROR: "crypto_blkcipher_type" [crypto/arc4.ko] undefined!
|ERROR: "blkcipher_walk_done" [crypto/arc4.ko] undefined!
|ERROR: "blkcipher_walk_virt" [crypto/arc4.ko] undefined!

Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 02e3037..a323805 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -604,7 +604,7 @@
 
 config CRYPTO_ARC4
 	tristate "ARC4 cipher algorithm"
-	select CRYPTO_ALGAPI
+	select CRYPTO_BLKCIPHER
 	help
 	  ARC4 cipher algorithm.