Added xfs support, parameter mount_options

[dsvetl]

Hello,

I added two small feature:

• Added support for xfs filesystem.
• Added options for pass mount options (e.g. compress=zstd).

I am using Shell Parameter Expansion to resolve problem in #59.

${parameter:+word}
If parameter is null or unset, nothing is substituted,
otherwise the expansion of word is substituted.

[gh2o]

Looks good. Can you update components/base-install.sh, then re-run tools/build_self_contained_install.sh to rebuild install.sh? Thanks!