Fix Make dependency file names

rules.mk

@@ -340,7 +340,8 @@ LST = $(patsubst %.c,$(OBJDIR)/%.lst,$(patsubst %.cpp,$(OBJDIR)/%.lst,$(patsubst
 
 
 # Compiler flags to generate dependency files.
-GENDEPFLAGS = -MMD -MP -MF .dep/$(@F).d
+#GENDEPFLAGS = -MMD -MP -MF .dep/$(@F).d
+GENDEPFLAGS = -MMD -MP -MF .dep/$(subst /,_,$@).d
 
 
 # Combine all necessary flags and optional flags.