pkg-python: no longer use distutilscross for setuptools

Thanks to the bump of Python 2.x, distutilscross is no longer needed
to achieve cross-compilation for setuptools packages. The host Python
2.x interpreter can be tricked into using the target compiler thanks
to pointing it to a different sysconfigdata module, which is achieved
using PYTHON_PATH.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/pkg-python.mk

@@ -114,7 +114,7 @@ endif
 else ifeq ($$($(2)_SETUP_TYPE),setuptools)
 ifeq ($(4),target)
 $(2)_BASE_ENV         = $$(PKG_PYTHON_SETUPTOOLS_ENV)
-$(2)_BASE_BUILD_TGT   = build -x
+$(2)_BASE_BUILD_TGT   = build
 $(2)_BASE_BUILD_OPT   =
 $(2)_BASE_INSTALL_OPT = $$(PKG_PYTHON_SETUPTOOLS_INSTALL_OPT)
 else
@@ -133,13 +133,12 @@ endif
 # front of the dependencies.
 #
 # However it must be repeated from inner-generic-package, as we need
-# to exclude the python, host-python, host-python-setuptools and
-# host-distutilscross packages, which are added below in the list of
-# dependencies depending on the package characteristics, and shouldn't
-# be derived automatically from the dependencies of the corresponding
-# target package. For example, target packages need
-# host-python-distutilscross, but not host packages.
-$(2)_DEPENDENCIES ?= $(filter-out host-python host-python-setuptools host-python-distutilscross host-toolchain $(1),$(patsubst host-host-%,host-%,$(addprefix host-,$($(3)_DEPENDENCIES))))
+# to exclude the python, host-python and host-python-setuptools
+# packages, which are added below in the list of dependencies
+# depending on the package characteristics, and shouldn't be derived
+# automatically from the dependencies of the corresponding target
+# package.
+$(2)_DEPENDENCIES ?= $(filter-out host-python host-python-setuptools host-toolchain $(1),$(patsubst host-host-%,host-%,$(addprefix host-,$($(3)_DEPENDENCIES))))
 
 # Target packages need both the python interpreter on the target (for
 # runtime) and the python interpreter on the host (for
@@ -152,17 +151,13 @@ $(2)_DEPENDENCIES += host-python
 endif
 
 # Setuptools based packages will need host-python-setuptools (both
-# host and target) and host-python-distutilscross (only target
-# packages). We need to have a special exclusion for the
+# host and target). We need to have a special exclusion for the
 # host-setuptools package itself: it is setuptools-based, but
 # shouldn't depend on host-setuptools (because it would otherwise
 # depend on itself!).
 ifeq ($$($(2)_SETUP_TYPE),setuptools)
 ifneq ($(2),HOST_PYTHON_SETUPTOOLS)
 $(2)_DEPENDENCIES += host-python-setuptools
-ifeq ($(4),target)
-$(2)_DEPENDENCIES += host-python-distutilscross
-endif
 endif
 endif