Revert "Removed unused structure"

This reverts commit e7dab5d210.

include/types.h

@@ -665,6 +665,23 @@ typedef enum user_options_map
  * structs
  */
 
+typedef struct
+{
+  u8  digest_length;
+  u8  key_length;
+  u8  fanout;
+  u8  depth;
+  u32 leaf_length;
+  u32 node_offset;
+  u32 xof_length;
+  u8  node_depth;
+  u8  inner_length;
+  u8  reserved[14];
+  u8  salt[16];
+  u8  personnel[16];
+
+} blake2params_t;
+
 typedef struct
 {
   u64 h[8];