Now in Linus Git tree. [1] says:
Merge tag 'x86-boot-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: "The main change in this cycle was to add support for ZSTD-compressed kernel and initrd images. ZSTD has a very fast decompressor, yet it compresses better than gzip" - Sedat - [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c0dfadfed87489fa6126ece161a14c2d15dbdc79
