[coreboot] [PATCH] BUILD: add -MMD to iasl cpp call

[Sven Schnelle]

Right now there are no dependency rules for compiling dsdt.asl.
If ACPI code includes asl files, the dsdt isn't recompiled if any
of those file is changed. Add the flags to the preprocessor call
to have it generate the neccessary dependency rule.

Signed-off-by: Sven Schnelle <svens at stackframe.org>
---
 Makefile.inc |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/Makefile.inc b/Makefile.inc
index 1d2d0dc..791150c 100644
--- a/Makefile.inc
+++ b/Makefile.inc
@@ -59,7 +59,7 @@ driver-S-ccopts:=-DASSEMBLY
 define ramstage-objs_asl_template
 $(obj)/$(1).ramstage.o: src/$(1).asl
 	@printf "    IASL       $$(subst $(top)/,,$$(@))\n"
-	$(CPP) -D__ACPI__ -P -include $(abspath $(obj)/config.h) -I$(src) -I$(src)/mainboard/$(MAINBOARDDIR) $$< -o $$(basename $$@).asl
+	$(CPP) -MMD -MT $$(@) -D__ACPI__ -P -include $(abspath $(obj)/config.h) -I$(src) -I$(src)/mainboard/$(MAINBOARDDIR) $$< -o $$(basename $$@).asl
 	iasl -p $$(obj)/$(1) -tc $$(basename $$@).asl
 	mv $$(obj)/$(1).hex $$(basename $$@).c
 	$(CC) $$(CFLAGS) $$(if $$(subst dsdt,,$$(basename $$(notdir $(1)))), -DAmlCode=AmlCode_$$(basename $$(notdir $(1)))) -c -o $$@ $$(basename $$@).c
-- 
1.7.4.1