Merge pull request #864 from alladinian/hotfix/secp256k1-header-imports

Author: yaroslavyaroslav

Sources/secp256k1/scalar_4x64_impl.h

@@ -3,6 +3,7 @@
  * Distributed under the MIT software license, see the accompanying   *
  * file COPYING or http://www.opensource.org/licenses/mit-license.php.*
  **********************************************************************/
+#include <sys/types.h>
 
 #ifndef SECP256K1_SCALAR_REPR_IMPL_H
 #define SECP256K1_SCALAR_REPR_IMPL_H