package/pkg-python.mk: switch back to local setuptools distutils

We overrode the default in 4386bbdf0895dbb35e02c25f42603bae9af64451 to
work around target shebang bug, as this issue no longer appears to be
present lets revert back to the local version as this is what will be
use in the future when distutils is removed from the python stdlib.

Tested with:
$ support/testing/run-tests -d dl -o output_folder -k tests.package.test_ipython.TestIPythonPy3
15:43:26 TestIPythonPy3                           Starting
15:43:27 TestIPythonPy3                           Building
15:49:35 TestIPythonPy3                           Building done
Downloading to /home/buildroot/buildroot/dl/tmp_iyk_fn6
Renaming from /home/buildroot/buildroot/dl/tmp_iyk_fn6 to /home/buildroot/buildroot/dl/kernel-versatile-5.10.7
Downloading to /home/buildroot/buildroot/dl/tmpokk23l2z
Renaming from /home/buildroot/buildroot/dl/tmpokk23l2z to /home/buildroot/buildroot/dl/versatile-pb-5.10.7.dtb
15:50:04 TestIPythonPy3                           Cleaning up
.
----------------------------------------------------------------------
Ran 1 test in 398.709s

OK

$ head -n 1 output_folder/TestIPythonPy3/target/usr/bin/ipython
#!/usr/bin/python

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>

package/pkg-python.mk

@@ -55,8 +55,7 @@ HOST_PKG_PYTHON_ENV = \
 # Target distutils-based packages
 PKG_PYTHON_DISTUTILS_ENV = \
 	$(PKG_PYTHON_ENV) \
-	LDSHARED="$(TARGET_CROSS)gcc -shared" \
-	SETUPTOOLS_USE_DISTUTILS=stdlib \
+	LDSHARED="$(TARGET_CROSS)gcc -shared"
 
 PKG_PYTHON_DISTUTILS_BUILD_OPTS = \
 	--executable=/usr/bin/python
@@ -75,16 +74,14 @@ PKG_PYTHON_DISTUTILS_INSTALL_STAGING_OPTS = \
 
 # Host distutils-based packages
 HOST_PKG_PYTHON_DISTUTILS_ENV = \
-	$(HOST_PKG_PYTHON_ENV) \
-	SETUPTOOLS_USE_DISTUTILS=stdlib
+	$(HOST_PKG_PYTHON_ENV)
 
 HOST_PKG_PYTHON_DISTUTILS_INSTALL_OPTS = \
 	--prefix=$(HOST_DIR)
 
 # Target setuptools-based packages
 PKG_PYTHON_SETUPTOOLS_ENV = \
-	$(PKG_PYTHON_ENV) \
-	SETUPTOOLS_USE_DISTUTILS=stdlib
+	$(PKG_PYTHON_ENV)
 
 PKG_PYTHON_SETUPTOOLS_CMD = \
 	$(if $(wildcard $($(PKG)_BUILDDIR)/setup.py),setup.py,-c 'from setuptools import setup;setup()')
@@ -105,8 +102,7 @@ PKG_PYTHON_SETUPTOOLS_INSTALL_STAGING_OPTS = \
 
 # Host setuptools-based packages
 HOST_PKG_PYTHON_SETUPTOOLS_ENV = \
-	$(HOST_PKG_PYTHON_ENV) \
-	SETUPTOOLS_USE_DISTUTILS=stdlib
+	$(HOST_PKG_PYTHON_ENV)
 
 HOST_PKG_PYTHON_SETUPTOOLS_INSTALL_OPTS = \
 	--prefix=$(HOST_DIR) \