hdrs: Fixup reinclusion preprocessor constants

Make them look like __CR_<smth>_H__ with

sed -e '1,2s/#\(ifndef\|define\) _\?_\?\(CR_\)\?/#\1 __CR_/' -e '1,2s/_H_\?_\?.*$/_H__/'

on every header file.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>