cpplib.c (cpp_options_init): Initialize cplusplus_comments to 1, matching July 18, 1995 change to cccp.c.

        * cpplib.c (cpp_options_init): Initialize cplusplus_comments to 1,
        matching July 18, 1995 change to cccp.c.  If -traditional then
        disable cplusplus_comments.

Co-Authored-By: Jeffrey A Law <law@cygnus.com>

From-SVN: r20960