unify HOST_CFLAGS and HOSTCFLAGS

The top build system sets up HOSTCFLAGS a bit and exports it, but other
places use HOST_CFLAGS instead.  Unify the two as HOSTCFLAGS so that the
values stay in sync.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

rules.mk

diff --git a/rules.mk b/rules.mk
index a77451b..6f999dd 100644
--- a/rules.mk
+++ b/rules.mk
@@ -29,7 +29,7 @@
 		@rm -f $@
 		@for f in $(SRCS); do \
 			g=`basename $$f | sed -e 's/\(.*\)\.\w/\1.o/'`; \
-			$(CC) -M $(HOST_CFLAGS) $(CPPFLAGS) -MQ $(obj)$$g $$f >> $@ ; \
+			$(CC) -M $(HOSTCFLAGS) $(CPPFLAGS) -MQ $(obj)$$g $$f >> $@ ; \
 		done
 
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