ubifs: Constify struct inode pointer in ubifs_crypt_is_encrypted()

...and provide a non const variant for fscrypto

Signed-off-by: Richard Weinberger <richard@nod.at>

fs/ubifs/super.c

@@ -2000,7 +2000,7 @@ static struct ubifs_info *alloc_ubifs_info(struct ubi_volume_desc *ubi)
 
 #ifndef CONFIG_UBIFS_FS_ENCRYPTION
 struct fscrypt_operations ubifs_crypt_operations = {
-	.is_encrypted		= ubifs_crypt_is_encrypted,
+	.is_encrypted		= __ubifs_crypt_is_encrypted,
 };
 #endif