cifs: make CIFS depend on CRYPTO_ECB

When CONFIG_CRYPTO_ECB is not set, trying to mount a CIFS share with NTLM
security resulted in mount failure with the following error:
   "CIFS VFS: could not allocate des crypto API"

Seems like a leftover from commit 43988d76.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
CC: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

fs/cifs/Kconfig

@@ -7,6 +7,7 @@ config CIFS
 	select CRYPTO_MD5
 	select CRYPTO_HMAC
 	select CRYPTO_ARC4
+	select CRYPTO_ECB
 	select CRYPTO_DES
 	help
 	  This is the client VFS module for the Common Internet File System