Rework CFLAGS
Rework CFLAGS

- Use CMAKE_CXX_FLAGS for compiler flags and add_definitions for
  definitions (-D).
- simplify flag selection logic.

git-svn-id: 5398946ba177a3e438c2dae55e2cdfc2fb96c905@4080 a9d63959-f2ad-4865-b262-bf0e56cfafb6

shyamalschandra/pcl,closerbibi/pcl,chatchavan/pcl,KevenRing/vlp,nh2/pcl,mikhail-matrosov/pcl,drmateo/pcl,jeppewalther/kinfu_segmentation,zavataafnan/pcl-truck,v4hn/pcl,the-glu/pcl,fanxiaochen/mypcltest,shangwuhencc/pcl,soulsheng/pcl,ResByte/pcl,wgapl/pcl,LZRS/pcl,shyamalschandra/pcl,damienjadeduff/pcl,drmateo/pcl,KevenRing/vlp,jeppewalther/kinfu_segmentation,chatchavan/pcl,simonleonard/pcl,lydhr/pcl,raydtang/pcl,msalvato/pcl_kinfu_highres,nikste/pcl,Nerei/pcl_old_repo,chenxingzhe/pcl,zhangxaochen/pcl,shyamalschandra/pcl,locnx1984/pcl,chatchavan/pcl,kanster/pcl,ResByte/pcl,the-glu/pcl,RufaelDev/pcc-mp3dg,shivmalhotra/pcl,RufaelDev/pcc-mp3dg,raydtang/pcl,sbec/pcl,lebronzhang/pcl,stfuchs/pcl,RufaelDev/pcc-mp3dg,closerbibi/pcl,zavataafnan/pcl-truck,shivmalhotra/pcl,mschoeler/pcl,zhangxaochen/pcl,fskuka/pcl,srbhprajapati/pcl,RufaelDev/pcc-mp3dg,the-glu/pcl,fanxiaochen/mypcltest,Tabjones/pcl,zhangxaochen/pcl,mikhail-matrosov/pcl,jeppewalther/kinfu_segmentation,wgapl/pcl,mikhail-matrosov/pcl,jakobwilm/pcl,lydhr/pcl,mschoeler/pcl,mschoeler/pcl,v4hn/pcl,kanster/pcl,fskuka/pcl,fskuka/pcl,KevenRing/pcl,nh2/pcl,MMiknis/pcl,v4hn/pcl,sbec/pcl,chatchavan/pcl,the-glu/pcl,msalvato/pcl_kinfu_highres,Tabjones/pcl,locnx1984/pcl,stefanbuettner/pcl,stfuchs/pcl,krips89/pcl_newfeatures,3dtof/pcl,soulsheng/pcl,ResByte/pcl,srbhprajapati/pcl,damienjadeduff/pcl,damienjadeduff/pcl,kanster/pcl,shangwuhencc/pcl,fanxiaochen/mypcltest,jeppewalther/kinfu_segmentation,3dtof/pcl,LZRS/pcl,zavataafnan/pcl-truck,KevenRing/pcl,sbec/pcl,ipa-rmb/pcl,lydhr/pcl,chenxingzhe/pcl,simonleonard/pcl,ResByte/pcl,DaikiMaekawa/pcl,shivmalhotra/pcl,stefanbuettner/pcl,KevenRing/vlp,wgapl/pcl,ipa-rmb/pcl,damienjadeduff/pcl,fskuka/pcl,nh2/pcl,simonleonard/pcl,cascheberg/pcl,starius/pcl,srbhprajapati/pcl,fskuka/pcl,the-glu/pcl,lydhr/pcl,cascheberg/pcl,sbec/pcl,jeppewalther/kinfu_segmentation,starius/pcl,sbec/pcl,LZRS/pcl,jakobwilm/pcl,krips89/pcl_newfeatures,DaikiMaekawa/pcl,soulsheng/pcl,soulsheng/pcl,krips89/pcl_newfeatures,soulsheng/pcl,raydtang/pcl,kanster/pcl,zavataafnan/pcl-truck,lebronzhang/pcl,Tabjones/pcl,zhangxaochen/pcl,ipa-rmb/pcl,pkuhto/pcl,chenxingzhe/pcl,drmateo/pcl,chenxingzhe/pcl,pkuhto/pcl,stfuchs/pcl,nikste/pcl,v4hn/pcl,lydhr/pcl,ipa-rmb/pcl,jakobwilm/pcl,closerbibi/pcl,cascheberg/pcl,shangwuhencc/pcl,msalvato/pcl_kinfu_highres,chenxingzhe/pcl,MMiknis/pcl,RufaelDev/pcc-mp3dg,damienjadeduff/pcl,KevenRing/vlp,Tabjones/pcl,fanxiaochen/mypcltest,lebronzhang/pcl,nh2/pcl,raydtang/pcl,MMiknis/pcl,3dtof/pcl,ipa-rmb/pcl,zhangxaochen/pcl,LZRS/pcl,closerbibi/pcl,lebronzhang/pcl,shangwuhencc/pcl,3dtof/pcl,Nerei/pcl_old_repo,zavataafnan/pcl-truck,locnx1984/pcl,mikhail-matrosov/pcl,Nerei/pcl_old_repo,starius/pcl,mikhail-matrosov/pcl,shangwuhencc/pcl,fanxiaochen/mypcltest,Tabjones/pcl,DaikiMaekawa/pcl,msalvato/pcl_kinfu_highres,stefanbuettner/pcl,mschoeler/pcl,lebronzhang/pcl,mschoeler/pcl,starius/pcl,srbhprajapati/pcl,jakobwilm/pcl,kanster/pcl,shyamalschandra/pcl,stfuchs/pcl,KevenRing/pcl,msalvato/pcl_kinfu_highres,v4hn/pcl,KevenRing/pcl,srbhprajapati/pcl,KevenRing/pcl,KevenRing/vlp,ResByte/pcl,MMiknis/pcl,jakobwilm/pcl,pkuhto/pcl,drmateo/pcl,wgapl/pcl,krips89/pcl_newfeatures,DaikiMaekawa/pcl,LZRS/pcl,nikste/pcl,closerbibi/pcl,pkuhto/pcl,MMiknis/pcl,pkuhto/pcl,nikste/pcl,shivmalhotra/pcl,locnx1984/pcl,locnx1984/pcl,3dtof/pcl,drmateo/pcl,starius/pcl,stefanbuettner/pcl,stefanbuettner/pcl,krips89/pcl_newfeatures,cascheberg/pcl,raydtang/pcl,shivmalhotra/pcl,Nerei/pcl_old_repo,stfuchs/pcl,cascheberg/pcl,wgapl/pcl,shyamalschandra/pcl,nikste/pcl,simonleonard/pcl,simonleonard/pcl,DaikiMaekawa/pcl