iOS updated "make clean"

make clean now knows how to clean the iOS special part

Change-Id: If132172d95823754f0983241a8121d143fcc3007

Makefile.in

@@ -174,6 +174,9 @@ clean-host:
 	rm -fr $(TESTINSTALLDIR)
 	rm -fr $(INSTDIR)
 	rm -fr $(WORKDIR)
+ifeq ($(OS),IOS)
+	rm -fr $(SRCDIR)/ios/generated
+endif
 
 clean-build:
 ifneq ($(CROSS_COMPILING),)