python*: upstream patches to fix with glibc-2.25

https://bugs.python.org/issue29157
The 3.6 release already contains the fix (from 3.5);
the branches in-between are claimed to be unaffected.
/cc #22874.

pkgs/development/interpreters/python/cpython/3.5/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl
+{ stdenv, fetchurl, fetchpatch
 , bzip2
 , gdbm
 , lzma
@@ -55,6 +55,14 @@ in stdenv.mkDerivation {
     substituteInPlace configure --replace '-Wl,-stack_size,1000000' ' '
   '';
 
+  patches = [
+    (fetchpatch {
+      name = "glibc-2.25-enosys.patch";
+      url = https://github.com/python/cpython/commit/035ba5da3e53e.patch;
+      sha256 = "1y74ir1w5cq542w27rgzgp70chhq2x047db9911mihpab8p2nj71";
+    })
+  ];
+
   postPatch = optionalString (x11Support && (tix != null)) ''
     substituteInPlace "Lib/tkinter/tix.py" --replace "os.environ.get('TIX_LIBRARY')" "os.environ.get('TIX_LIBRARY') or '${tix}/lib'"
   '';