Reverted Makevars and Makevars.in

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/geometry@127 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Another attempt to fix Issue #5406: Comilation flags in Makevars

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/geometry@128 edb9625f-4e0d-4859-8d74-9fd3b1da38cb