[Patch, Fortran] PR34186 -fdump-parse-tree fixes

[FX Coudert]

:REVIEWMAIL:

> 2007-11-30  Tobias Burnus  <burnus@net-b.de>
>
> 	PR fortran/34186
> 	* symbol.c (generate_isocbinding_symbol): Set string length.
> 	* dump-parse-tree.c (gfc_show_attr): Show BIND(C) attribute.
> 	* misc.c (gfc_basic_typename): Handle BT_VOID.

OK.