Fixed gcc 7.2 "statement will never be executed" warning
Fixed gcc 7.2 "statement will never be executed" warning

azonenberg/yosys,cliffordwolf/yosys,YosysHQ/yosys,SymbiFlow/yosys,cliffordwolf/yosys,cliffordwolf/yosys,antmicro/yosys,antmicro/yosys,antmicro/yosys,azonenberg/yosys,azonenberg/yosys,cliffordwolf/yosys,antmicro/yosys,SymbiFlow/yosys,SymbiFlow/yosys,SymbiFlow/yosys,cliffordwolf/yosys,SymbiFlow/yosys,azonenberg/yosys,azonenberg/yosys,cliffordwolf/yosys,SymbiFlow/yosys,SymbiFlow/yosys,YosysHQ/yosys,cliffordwolf/yosys,azonenberg/yosys,azonenberg/yosys,YosysHQ/yosys,YosysHQ/yosys,antmicro/yosys,YosysHQ/yosys,azonenberg/yosys,antmicro/yosys,YosysHQ/yosys,YosysHQ/yosys,YosysHQ/yosys,azonenberg/yosys,antmicro/yosys,cliffordwolf/yosys,antmicro/yosys,SymbiFlow/yosys,cliffordwolf/yosys