* rust-demangle.c (unescape): Remove.
	(parse_lower_hex_nibble): New function.
	(parse_legacy_escape): New function.
	(is_prefixed_hash): Use parse_lower_hex_nibble.
	(looks_like_rust): Use parse_legacy_escape.
	(rust_demangle_sym): Use parse_legacy_escape.
	* testsuite/rust-demangle-expected: Add 'llv$u6d$' test.

From-SVN: r275353