cppinit.c (cpp_read_main_file): Split out source-independent initialization to separa...

cppinit.c (cpp_read_main_file): Split out source-independent initialization to separate function ...

        * cppinit.c (cpp_read_main_file):  Split out source-independent
        initialization to separate function ...
        (cpp_post_options):  New function.
        * cppfiles.c (cpp_stack_file):  Rename public name to ...
        (_cpp_stack_file):  New internal function name.
        * cpplib.h:  Update accordingly.
        * cppinit.c:  (cpp_create_reader):  Initialize cpp_readers line here.
        (cpp_read_main_file):  Don't initialize line here.
        * c-opts.c (c_common_post_options):  Call cpp_post_options.
        (c_common_parse_file):  Call cpp_read_main_file, not cpp_stack_file.
        * fix-header.c (read_scan_file):  Call cpp_post_options.

From-SVN: r70279