ext4 crypto: require CONFIG_CRYPTO_CTR if ext4 encryption is enabled

On arm64 this is apparently needed for CTS mode to function correctly.
Otherwise attempts to use CTS return ENOENT.

Change-Id: I732ea9a5157acc76de5b89edec195d0365f4ca63
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

fs/ext4/Kconfig

@@ -72,6 +72,7 @@ config EXT4_ENCRYPTION
 	select CRYPTO_ECB
 	select CRYPTO_XTS
 	select CRYPTO_CTS
+	select CRYPTO_CTR
 	select CRYPTO_SHA256
 	select KEYS
 	select ENCRYPTED_KEYS