more platforms.gnu -> gnu ++ linux changes, manually

pkgs/development/compilers/mit-scheme/default.nix

@@ -87,6 +87,6 @@ stdenv.mkDerivation {
 
     # Build fails on Cygwin and Darwin:
     # <http://article.gmane.org/gmane.lisp.scheme.mit-scheme.devel/489>.
-    platforms = platforms.gnu ++ platforms.freebsd;
+    platforms = platforms.gnu ++ platforms.linux ++ platforms.freebsd;
   };
 }

pkgs/servers/http/myserver/default.nix

@@ -43,7 +43,7 @@ stdenv.mkDerivation rec {
     license = lib.licenses.gpl3Plus;
 
     # libevent fails to build on Cygwin and Guile has troubles on Darwin.
-    platforms = lib.platforms.gnu;
+    platforms = lib.platforms.gnu ++ lib.platforms.linux;
 
     broken = true; # needs patch for gets()
   };

pkgs/tools/networking/p2p/tahoe-lafs/default.nix

@@ -89,6 +89,6 @@ pythonPackages.buildPythonApplication rec {
     homepage = http://tahoe-lafs.org/;
     license = [ lib.licenses.gpl2Plus /* or */ "TGPPLv1+" ];
     maintainers = with lib.maintainers; [ MostAwesomeDude ];
-    platforms = lib.platforms.gnu;  # arbitrary choice
+    platforms = lib.platforms.gnu ++ lib.platforms.linux;
   };
 }