python: remove *.pyo files

Even though we disable the build of .pyo files in the interpreter,
nothing prevents other packages to install them. Since we only want to
keep either .py or .pyc or both, let's add a target finalize hooks
that removes all .pyo files.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
[Thomas: add --no-run-if-empty option to xargs, as suggested by Samuel.]
Reviewed-by: Samuel Martin <s.martin49@gmail.com>

package/python/python.mk

@@ -230,3 +230,11 @@ define PYTHON_REMOVE_PYC_FILES
 endef
 TARGET_FINALIZE_HOOKS += PYTHON_REMOVE_PYC_FILES
 endif
+
+# In all cases, we don't want to keep the optimized .pyo files
+ifeq ($(BR2_PACKAGE_PYTHON),y)
+define PYTHON_REMOVE_PYO_FILES
+	find $(TARGET_DIR)/usr/lib/python$(PYTHON_VERSION_MAJOR) -name '*.pyo' -print0 | xargs -0 --no-run-if-empty rm -f
+endef
+TARGET_FINALIZE_HOOKS += PYTHON_REMOVE_PYO_FILES
+endif