minimal: For frozen bytecode generation, add dependency of qstr file.

minimal/Makefile

@@ -60,9 +60,9 @@ else
 all: $(BUILD)/firmware.elf
 endif
 
-$(BUILD)/_frozen_mpy.c: frozentest.mpy
+$(BUILD)/_frozen_mpy.c: frozentest.mpy $(BUILD)/genhdr/qstrdefs.generated.h
 	$(ECHO) "MISC freezing bytecode"
-	$(Q)../tools/mpy-tool.py -f -q $(BUILD)/genhdr/qstrdefs.preprocessed.h -mlongint-impl=none $^ > $@
+	$(Q)../tools/mpy-tool.py -f -q $(BUILD)/genhdr/qstrdefs.preprocessed.h -mlongint-impl=none $< > $@
 
 $(BUILD)/firmware.elf: $(OBJ)
 	$(ECHO) "LINK $@"