cmake: add mkdir to the out-of-source build ex.
cmake: add mkdir to the out-of-source build ex.
felixonmars/tldr,Phizho/tldr,slash3b/tldr,felixonmars/tldr,UncommonPleb/tldr,UncommonPleb/tldr,katekyan/tldr,deekim/tldr,deekim/tldr,zoisom/tldr,katekyan/tldr,slash3b/tldr,slash3b/tldr,cptdeka10/tldr,UncommonPleb/tldr,cptdeka10/tldr,zoisom/tldr,Phizho/tldr,Phizho/tldr,katekyan/tldr,zoisom/tldr,cptdeka10/tldr,felixonmars/tldr,deekim/tldr