[TF wheel] Put tensorflow & third_party headers in the right directory (again).

Prior to this, headers meant to go into include/{third_party,tensorflow} were being
put into a tensorflow-xxx.data/purelib/include directory during bdist build.  Now they're
placed into tensorflow/include/ and the wheel installs them where they're expected.

PiperOrigin-RevId: 295990673
Change-Id: I0606c75780ae6cda93bc009d3aa5bf03e51e2734

tensorflow/tools/pip_package/setup.py

@@ -143,7 +143,7 @@ class InstallCommand(InstallCommandBase):
 
   def finalize_options(self):
     ret = InstallCommandBase.finalize_options(self)
-    self.install_headers = os.path.join(self.install_purelib, 'tensorflow',
+    self.install_headers = os.path.join(self.install_platlib, 'tensorflow',
                                         'include')
     self.install_lib = self.install_platlib
     return ret