firefox, spidermonkey: remove NIX_LDFLAGS

This commit reverts #210859, since aarch64-linux now uses GCC 12 by default.

pkgs/applications/networking/browsers/firefox/common.nix

@@ -471,9 +471,6 @@ buildStdenv.mkDerivation ({
   separateDebugInfo = enableDebugSymbols;
   enableParallelBuilding = true;
 
-  # https://github.com/NixOS/nixpkgs/issues/201254
-  NIX_LDFLAGS = if (with stdenv; isAarch64 && isLinux) then [ "-lgcc" ] else null;
-
   # tests were disabled in configureFlags
   doCheck = false;
 

pkgs/development/interpreters/spidermonkey/common.nix

@@ -136,9 +136,6 @@ stdenv.mkDerivation (finalAttrs: rec {
   # while we have a double-float toolchain
   env.NIX_CFLAGS_COMPILE = lib.optionalString (with stdenv.hostPlatform; isRiscV && is64bit && lib.versionOlder version "91") "-mabi=lp64d";
 
-  # https://github.com/NixOS/nixpkgs/issues/201254
-  NIX_LDFLAGS = if (with stdenv; isAarch64 && isLinux) then [ "-lgcc" ] else null;
-
   postPatch = lib.optionalString (lib.versionOlder version "102") ''
     # This patch is a manually applied fix of
     #   https://bugzilla.mozilla.org/show_bug.cgi?id=1644600