Don't pass -lc to Emscripten, it breaks

See:
emscripten-core/emscripten#22742
emscripten-core/emscripten#16680
rust-lang/rust#98155
rust-lang/rust#98303
rust-lang/rust#131885

(backport <rust-lang#4002>)
(cherry picked from commit 66e3665)

Author: hoodmane

src/unix/mod.rs

@@ -382,8 +382,8 @@ cfg_if! {
                    link(name = "c", cfg(not(target_feature = "crt-static"))))]
         extern {}
     } else if #[cfg(target_os = "emscripten")] {
-        #[link(name = "c")]
-        extern {}
+        // Don't pass -lc to Emscripten, it breaks. See:
+        // https://github.com/emscripten-core/emscripten/issues/22758
     } else if #[cfg(all(target_os = "android", feature = "rustc-dep-of-std"))] {
         #[link(name = "c", kind = "static", modifiers = "-bundle",
             cfg(target_feature = "crt-static"))]