There were two cases that were handled incorrectly:
- if the user hasn't entered a salinity, obviously there shouldn't be a warning
- if this is a manually entered dive, there is no salinity downloaded from a
dive computer, so equally, no warning
Suggested-by: willemferguson <willemferguson@zoology.up.ac.za>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>