remove .a files from lib directories after install

package/Makefile.autotools.in

@@ -231,6 +231,9 @@ $(BUILD_DIR)/%/.stamp_target_installed:
 		rm -rf $(TARGET_DIR)/$$d $(TARGET_DIR)/usr/$$d; \
 	done)
 	find $(TARGET_DIR) -name '*.la' -delete
+	find $(TARGET_DIR)/lib -name '*.a' -delete
+	find $(TARGET_DIR)/usr/lib -name '*.a' -delete
+
 	touch $@
 
 $(BUILD_DIR)/%/.stamp_cleaned: