Use rm -f flag in make clean

Makefile

@@ -48,7 +48,7 @@ setup:
 
 .PHONY: clean
 clean:
-	rm -r build/
+	rm -rf build/
 
 .PHONY: lcf
 lcf: setup $(TOOLS_DIR)/lcf.py

tools/compress/Makefile

@@ -16,7 +16,7 @@ endif
 all: $(OUTFILE)
 
 clean:
-	rm $(OUTFILE)
+	rm -f $(OUTFILE)
 
 $(OUTFILE): main.c
 	$(CC) $(CFLAGS) -o $(OUTFILE) main.c

tools/rom/Makefile

@@ -18,8 +18,8 @@ endif
 all: $(EXTRACTFILE) $(BUILDFILE)
 
 clean:
-	rm $(EXTRACTFILE)
-	rm $(BUILDFILE)
+	rm -f $(EXTRACTFILE)
+	rm -f $(BUILDFILE)
 
 $(EXTRACTFILE): extract.c
 	$(CC) $(CFLAGS) -o $(EXTRACTFILE) extract.c