Implement chr_close callback for "stdio" so that it can be closed and reopened. Free chr devices after they're closed. git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3927 c046a42c-6fe2-441c-8c8c-71466251a162
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3914 c046a42c-6fe2-441c-8c8c-71466251a162