Fix Blake2s overlapping writes

We are copying from a 32bit buffer, so are overlapping writes. This
could cause damage the hash on big-endian platforms.

Author: LinuxJedi

wolfcrypt/src/blake2s.c

@@ -365,7 +365,7 @@ int blake2s_final( blake2s_state *S, byte *out, byte outlen )
   }
 
   for( i = 0; i < 8; ++i ) /* Output full hash to temp buffer */
-    store64( buffer + sizeof( S->h[i] ) * i, S->h[i] );
+    store32( buffer + sizeof( S->h[i] ) * i, S->h[i] );
 
   XMEMCPY( out, buffer, outlen );