gccrs: Add location info to `Rust::Identifier`

gccrs: Add location info to `Rust::Identifier`

gcc/rust/ChangeLog:

	* ast/rust-ast.h: Modify constructors of `Rust::Identifier`
	* ast/rust-pattern.h: Likewise.
	* hir/tree/rust-hir-item.h: Likewise.
	* parse/rust-parse-impl.h (Parser::parse_macro_rules_def): Likewise.
	(Parser::parse_decl_macro_def): Likewise.
	(Parser::parse_macro_match_fragment): Likewise.
	(Parser::parse_module): Likewise.
	(Parser::parse_use_tree): Likewise.
	(Parser::parse_function): Likewise.
	(Parser::parse_type_param): Likewise.
	(Parser::parse_type_alias): Likewise.
	(Parser::parse_struct): Likewise.
	(Parser::parse_struct_field): Likewise.
	(Parser::parse_enum): Likewise.
	(Parser::parse_enum_item): Likewise.
	(Parser::parse_union): Likewise.
	(Parser::parse_static_item): Likewise.
	(Parser::parse_trait): Likewise.
	(Parser::parse_trait_item): Likewise.
	(Parser::parse_trait_type): Likewise.
	(Parser::parse_trait_const): Likewise.
	(Parser::parse_external_item): Likewise.
	(Parser::parse_generic_args_binding): Likewise.
	(Parser::parse_method): Likewise.
	(Parser::parse_maybe_named_param): Likewise.
	(Parser::parse_identifier_pattern): Likewise.
	(Parser::parse_struct_expr_field): Likewise.
	(ResolveItem::visit): Likewise.
	* typecheck/rust-hir-type-check-implitem.cc (TypeCheckImplItem::visit):Add comments
	* resolve/rust-ast-resolve-item.cc (ResolveTraitItems::visit): Likewise.
	* checks/lints/rust-lint-scan-deadcode.h: Fix error location

Signed-off-by: Raiki Tamura <tamaron1203@gmail.com>