python: expose PYTHON_PATH

As a preparation to make the Python infrastructure support both Python
and Python 3, as well as the bump of Python 2 and 3, we need the
Python package to expose the Python module path in a variable called
PYTHON_PATH. It will be used by the following commits.

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

package/python/python.mk

@@ -167,5 +167,8 @@ PYTHON_POST_INSTALL_TARGET_HOOKS += PYTHON_REMOVE_USELESS_FILES
 
 PYTHON_AUTORECONF = YES
 
+# Provided to other packages
+PYTHON_PATH = $(TARGET_DIR)/usr/lib/python$(PYTHON_VERSION_MAJOR)/site-packages/
+
 $(eval $(autotools-package))
 $(eval $(host-autotools-package))