Also change some internal variables and function arguments from int to bool.

gcc/ChangeLog:

    * dwarf2asm.cc: Change FALSE to false.
    * dwarf2cfi.cc (execute_dwarf2_frame): Change return type to void.
    * dwarf2out.cc (matches_main_base): Change return type from
    int to bool.  Change "last_match" variable to bool.
    (dump_struct_debug): Change return type from int to bool.
    Change "matches" and "result" function arguments to bool.
    (is_pseudo_reg): Change return type from int to bool.
    (is_tagged_type): Ditto.
    (same_loc_p): Ditto.
    (same_dw_val_p): Change return type from int to bool and adjust
    function body accordingly.
    (same_attr_p): Ditto.
    (same_die_p): Ditto.
    (is_type_die): Ditto.
    (is_declaration_die): Ditto.
    (should_move_die_to_comdat): Ditto.
    (is_base_type): Ditto.
    (is_based_loc): Ditto.
    (local_scope_p): Ditto.
    (class_scope_p): Ditto.
    (class_or_namespace_scope_p): Ditto.
    (is_tagged_type): Ditto.
    (is_rust): Use void argument.
    (is_nested_in_subprogram): Change return type from int to bool.
    (contains_subprogram_definition): Ditto.
    (gen_struct_or_union_type_die): Change "nested", "complete"
    and "ns_decl" variables to bool.
    (is_naming_typedef_decl): Change FALSE to false.

Bootstrapped and regression tested on x86_64-linux-gnu {,-m32}.

Uros.