python3: fix the value of PYTHON3_PATH

The PYTHON3_PATH was incorrectly referencing the site-packages of
Python 2 packages, due to the usage of PYTHON_VERSION_MAJOR, instead
of PYTHON3_VERSION_MAJOR. This commit fixes that by using the correct
variable, which in our testing fixed the build of python-pyasn against
python3.

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

package/python3/python3.mk

@@ -169,7 +169,7 @@ HOST_PYTHON3_POST_INSTALL_HOOKS += HOST_PYTHON3_INSTALL_SYMLINK
 endif
 
 # Provided to other packages
-PYTHON3_PATH = $(TARGET_DIR)/usr/lib/python$(PYTHON3_VERSION_MAJOR)/sysconfigdata/:$(TARGET_DIR)/usr/lib/python$(PYTHON_VERSION_MAJOR)/site-packages/
+PYTHON3_PATH = $(TARGET_DIR)/usr/lib/python$(PYTHON3_VERSION_MAJOR)/sysconfigdata/:$(TARGET_DIR)/usr/lib/python$(PYTHON_VERSION3_MAJOR)/site-packages/
 
 $(eval $(autotools-package))
 $(eval $(host-autotools-package))