The 'gasmix' argument to add_segment() is read-only

We'll want to use a 'static const' gasmix for the upcoming no-fly-time
code, so prepare for it by just marking the read-only gasmix argument as
'const'.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Updated Swedish translation

Some updates to the Swedish translation.

Signed-off-by: Fredrik Steen <fredrik@ppo2.se>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Fix duration calculation

Some days I'm just a f*cking moron. That code was so stupid that I'm
lacking words. I replaced using the first divecomputer with using the last
divecomputer. When what I wanted was to use the maximum duration.

This looks better.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>