chrono-tz-build: resolve fixme

linked issue foxed long ago rust-phf/rust-phf#232

Author: klensy

chrono-tz-build/src/lib.rs

@@ -142,10 +142,7 @@ fn write_timezone_file(timezone_file: &mut File, table: &Table) -> io::Result<()
         writeln!(
             timezone_file,
             "static TIMEZONES_UNCASED: ::phf::Map<&'static uncased::UncasedStr, Tz> = \n{};",
-            // FIXME(petrosagg): remove this once rust-phf/rust-phf#232 is released
             map.build()
-                .to_string()
-                .replace("::std::mem::transmute", "::core::mem::transmute")
         )?;
     }