use same airootfs_image_tool_options in baseline as in releng

configs/baseline/profiledef.sh

@@ -10,6 +10,7 @@ install_dir="arch"
 bootmodes=('bios.syslinux.mbr' 'bios.syslinux.eltorito' 'uefi-x64.systemd-boot.esp' 'uefi-x64.systemd-boot.eltorito')
 arch="x86_64"
 pacman_conf="pacman.conf"
+airootfs_image_tool_options=('-comp' 'xz' '-Xbcj' 'x86' '-b' '1M' '-Xdict-size' '1M')
 file_permissions=(
   ["/etc/shadow"]="0:0:400"
 )