ezsat: Fix build for emscripten/wasi

libs/ezsat/ezcommand.cc

@@ -9,6 +9,7 @@ ezSATCommand::~ezSATCommand() {}
 
 bool ezSATCommand::solver(const std::vector<int> &modelExpressions, std::vector<bool> &modelValues, const std::vector<int> &assumptions)
 {
+#if !defined(YOSYS_DISABLE_SPAWN)
 	const std::string tempdir_name = Yosys::make_temp_dir(Yosys::get_base_tmpdir() + "/yosys-sat-XXXXXX");
 	const std::string cnf_filename = Yosys::stringf("%s/problem.cnf", tempdir_name.c_str());
 	const std::string sat_command = Yosys::stringf("%s %s", command.c_str(), cnf_filename.c_str());
@@ -81,4 +82,7 @@ bool ezSATCommand::solver(const std::vector<int> &modelExpressions, std::vector<
 		modelValues[i] = (values.at(idx - 1) == refvalue);
 	}
 	return true;
+#else
+	Yosys::log_error("SAT solver command not available in this build!\n");
+#endif
 }