Remove is_air() and convert its users to gasmix

Also make gasname() and get_gas_string() global functions (which allows us
to delete code elsewhere).

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

1 files changed, 1 insertions, 1 deletions

diff --git a/dive.c b/dive.c
index aad4b07a5..9cfdfc14a 100644
--- a/dive.c
+++ b/dive.c
@@ -546,7 +546,7 @@ void sanitize_gasmix(struct gasmix *mix)
 		if (!o2)
 			return;
 		/* 20.8% to 21% O2 is just air */
-		if (is_air(o2, he)) {
+		if (gasmix_is_air(mix)) {
 			mix->o2.permille = 0;
 			return;
 		}