detect_virt segment shows false positive "chroot" for btrfs

[piggynl]

powerlevel10k/internal/p10k.zsh

Lines 2274 to 2285 in cf83ab2

	prompt_detect_virt() {
	local virt="$(systemd-detect-virt 2>/dev/null)"
	if [[ "$virt" == "none" ]]; then
	local -a inode
	if zstat -A inode +inode / 2>/dev/null && [[ $inode[1] != 2 ]]; then
	virt="chroot"
	fi
	fi
	if [[ -n "${virt}" ]]; then
	_p9k_prompt_segment "$0" "$_p9k_color1" "yellow" '' 0 '' "${virt//\%/%%}"
	fi
	}

Btrfs subvolumes always have inode number 256 instead of 2, so detect_virt segment will show false positive "chroot" for btrfs.

Maybe we can check the return value of unshare -U true to determine whether we are in chroot? But it will be much slower :(