Convenient for qemu debugging and adding ci check
We can learn to use the following command to mount 9pfs on qemu64:
qemu-system-aarch64 -cpu max -nographic \
-machine virt,virtualization=on,gic-version=3,mte=on \
-fsdev local,security_model=none,id=fsdev0,path=/xxxx -device virtio-9p-device,id=fs0,fsdev=fsdev0,mount_tag=host \
-chardev stdio,id=con,mux=on, -serial chardev:con \
-mon chardev=con,mode=readline -kernel ./nuttx/nutt
mkdir mnt
mount -t v9fs -o trans=virtio,tag=host mnt
Signed-off-by: wangmingrong1 <wangmingrong1@xiaomi.com>