Merge "build_system: Prevent goals needing makeopts from running when it's missing"

Makefile

@@ -100,7 +100,10 @@ export LDCONFIG
 export LDCONFIG_FLAGS
 export PYTHON
 
--include makeopts
+# makeopts is required unless the goal is clean or distclean
+ifeq ($(findstring clean,$(MAKECMDGOALS)),)
+include makeopts
+endif
 
 # start the primary CFLAGS and LDFLAGS with any that were provided
 # to the configure script