Fix c_backend app compilation with CMake.
Fix c_backend app compilation with CMake.

dougkwan/Halide,delcypher/Halide,smxlong/Halide,delcypher/Halide,kgnk/Halide,dan-tull/Halide,kenkuang1213/Halide,kgnk/Halide,dan-tull/Halide,mcanthony/Halide,ronen/Halide,adasworks/Halide,tdenniston/Halide,ayanazmat/Halide,aam/Halide,adasworks/Halide,delcypher/Halide,aam/Halide,jiawen/Halide,rodrigob/Halide,dougkwan/Halide,ronen/Halide,damienfir/Halide,tdenniston/Halide,rodrigob/Halide,adasworks/Halide,kenkuang1213/Halide,psuriana/Halide,smxlong/Halide,jiawen/Halide,lglucin/Halide,ronen/Halide,damienfir/Halide,lglucin/Halide,kenkuang1213/Halide,myrtleTree33/Halide,myrtleTree33/Halide,dougkwan/Halide,smxlong/Halide,kgnk/Halide,dougkwan/Halide,rodrigob/Halide,kenkuang1213/Halide,fengzhyuan/Halide,smxlong/Halide,damienfir/Halide,ayanazmat/Halide,damienfir/Halide,adasworks/Halide,psuriana/Halide,kgnk/Halide,ronen/Halide,ayanazmat/Halide,psuriana/Halide,adasworks/Halide,dougkwan/Halide,ronen/Halide,myrtleTree33/Halide,mcanthony/Halide,delcypher/Halide,kgnk/Halide,rodrigob/Halide,dan-tull/Halide,fengzhyuan/Halide,fengzhyuan/Halide,dan-tull/Halide,dan-tull/Halide,lglucin/Halide,aam/Halide,myrtleTree33/Halide,ronen/Halide,damienfir/Halide,adasworks/Halide,damienfir/Halide,delcypher/Halide,ayanazmat/Halide,kgnk/Halide,tdenniston/Halide,kenkuang1213/Halide,dougkwan/Halide,fengzhyuan/Halide,tdenniston/Halide,fengzhyuan/Halide,psuriana/Halide,smxlong/Halide,kenkuang1213/Halide,smxlong/Halide,jiawen/Halide,rodrigob/Halide,psuriana/Halide,fengzhyuan/Halide,dougkwan/Halide,ayanazmat/Halide,mcanthony/Halide,dan-tull/Halide,lglucin/Halide,jiawen/Halide,ayanazmat/Halide,mcanthony/Halide,delcypher/Halide,dan-tull/Halide,ayanazmat/Halide,psuriana/Halide,mcanthony/Halide,kgnk/Halide,tdenniston/Halide,ronen/Halide,myrtleTree33/Halide,kgnk/Halide,aam/Halide,myrtleTree33/Halide,aam/Halide,tdenniston/Halide,adasworks/Halide,myrtleTree33/Halide,damienfir/Halide,fengzhyuan/Halide,dan-tull/Halide,fengzhyuan/Halide,smxlong/Halide,jiawen/Halide,myrtleTree33/Halide,lglucin/Halide,tdenniston/Halide,jiawen/Halide,adasworks/Halide,rodrigob/Halide,damienfir/Halide,jiawen/Halide,rodrigob/Halide,tdenniston/Halide,mcanthony/Halide,smxlong/Halide,lglucin/Halide,aam/Halide,delcypher/Halide,ayanazmat/Halide,psuriana/Halide,mcanthony/Halide,mcanthony/Halide,dougkwan/Halide,lglucin/Halide,rodrigob/Halide,kenkuang1213/Halide,ronen/Halide,delcypher/Halide,kenkuang1213/Halide,aam/Halide