Add rb_parser_set_pos function

[S-H-GAMELINKS]

rb_parser_set_location_from_strterm_heredoc, rb_parser_set_location_of_none and rb_parser_set_location functions has similar code(like this).

    yylloc->beg_pos.lineno = p->ruby_sourceline;
    yylloc->beg_pos.column = (int)(p->lex.ptok - p->lex.pbeg);
    yylloc->end_pos.lineno = p->ruby_sourceline;
    yylloc->end_pos.column = (int)(p->lex.pcur - p->lex.pbeg);
    return yylloc;

I think better to cut out these similar code to function like rb_parser_set_pos, but how about it?

YYLTYPE *
rb_parser_set_pos(YYLTYPE *yylloc, int sourceline, int beg_pos, int end_pos)
{
    yylloc->beg_pos.lineno = sourceline;
    yylloc->beg_pos.column = beg_pos;
    yylloc->end_pos.lineno = sourceline;
    yylloc->end_pos.column = end_pos;
    return yylloc;
}

[nobu]

Why is rb_parser_set_pos global?

[S-H-GAMELINKS]

@nobu

Why is rb_parser_set_pos global?

Sorry, I forgot add static modifier.