dtc: Add missing dependencies for tests

At present, the Makefiles will not rebuild trees.o or the dtb files
derived from it if testdata.h is updated.  This is incorrect, and is
because of missing dependency information.

This patch fixes the problem by making sure that dependency
information is generated from trees.S and dumptrees.c.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Makefile

@@ -188,6 +188,10 @@ clean: libfdt_clean tests_clean
 	@$(VECHO) DEP $<
 	$(CC) $(CPPFLAGS) -MM -MG -MT "$*.o $@" $< > $@
 
+%.d: %.S
+	@$(VECHO) DEP $<
+	$(CC) $(CPPFLAGS) -MM -MG -MT "$*.o $@" $< > $@
+
 %.i:	%.c
 	@$(VECHO) CPP $@
 	$(CC) $(CPPFLAGS) -E $< > $@

tests/Makefile.tests

@@ -21,7 +21,8 @@ TESTS_TREES = $(TESTS_TREES_L:%=$(TESTS_PREFIX)%)
 
 TESTS_TARGETS = $(TESTS) $(TESTS_TREES)
 
-TESTS_DEPFILES = $(TESTS:%=%.d) $(TESTS_PREFIX)testutils.d
+TESTS_DEPFILES = $(TESTS:%=%.d) \
+	$(addprefix $(TESTS_PREFIX),testutils.d trees.d dumptrees.d)
 
 TESTS_CLEANFILES_L =  *.output vgcore.* *.dtb *.test.dts
 TESTS_CLEANFILES = $(TESTS_CLEANFILES_L:%=$(TESTS_PREFIX)%)