We still need to export gb_Side for host platform

..where makefiles are not just included.

Change-Id: I9c5590c1c846d88955ee153f2af786df020ef991

Makefile.in

@@ -46,7 +46,7 @@ else # MAKE_RESTARTS
 all: build
 
 ifeq ($(gb_Side),)
-gb_Side:=host
+export gb_Side:=host
 endif
 
 include $(BUILDDIR)/config_$(gb_Side).mk