message: fix JS's glue, call the right function
diff: @@ -195,7 +195,7 @@ export const spend = (module, wallet, inputs, outputs, fee_addr) => {
  const bufinput = newArray(module, input_array);
  const bufoutput = newArray0(module, 4096);
  - let rsz = module.xwallet_create(bufinput, input_array.length, bufoutput);
  + let rsz = module.xwallet_spend(bufinput, input_array.length, bufoutput);
  let output_array = copyArray(module, bufoutput, rsz);
  module.dealloc(bufoutput);
  