Bug #11667

Updated by Toomas Soome over 4 years ago

Use one lz4 implementation. That is, move uts/common/fs/zfs/lz4.c to common/lz4/, patch it up to be buildable from kernel, loader and userland and remove unused static bits + comments. 

 Build cleanups are based on gcc (7,9) and clang80 notes (oi and freebsd) - mostly concerning about alignment changes, const vs non-const. 

 Testing done: build/install/boot. I have compression=on so the pool access is immediately tested by loader and kernel zfs; the built in loader font and softcore dictionary is decompressed, so both build time compress and boot time decompress are also tested by boot.