It is consistent with other compressors also using their
best compression.
xz is currently the option that offers best compression,
using settings even lower than the default is surprising
and makes it harder to choose the best available compression.
For anyone who cares about compression time using a different
option like gzip or bzip2 is the logical choice.
For decompression, better compressed is actually faster
to decompress.
Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
