Add target run-nox-<program>

This target allows starting ucore with the specified user program in
pure terminal.

Signed-off-by: Junjie Mao <junjie.mao@hotmail.com>

labcodes_answer/lab8_result/Makefile

@@ -335,6 +335,9 @@ run-%: build-%
 sh-%: script-%
 	$(V)$(QEMU) -parallel stdio $(QEMUOPTS) -serial null
 
+run-nox-%: build-%
+	$(V)$(QEMU) -serial mon:stdio $(QEMUOPTS) -nographic
+
 build-%: touch
 	$(V)$(MAKE) $(MAKEOPTS) "DEFS+=-DTEST=$*"