wallet: Fix clang build in Mac
wallet: Fix clang build in Mac

Signed-off-by: Anthony Fieroni <bvbfan@abv.bg>

Former-commit-id: baf8b01c56a7f548d3620b6dd8cedf81811d6858
syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin