fix: make scent_modifier affect your scent equilibrium. (#5323)

Update character_turn.cpp

`scent_modifier` was multiplying the scent value after addition/subtraction. Meaning that if you had a value less than 0 and just created the character/loaded it, the scent map would be 0 and increased to 1, then multiplied by 0.x which is then truncated to 0.

Fixes it so it actually multplies your `norm_scent` value.

src/character_turn.cpp

@@ -239,9 +239,14 @@ void Character::process_turn()
             }
         }
 
-        //mask from scent altering items;
+        // Mask from scent altering items;
         norm_scent += mask_intensity;
 
+        // Now that all the additions are done, multiply norm_scent by any scent modifiers.
+        for( const trait_id &mut : get_mutations() ) {
+            norm_scent *= mut.obj().scent_modifier;
+        }
+
         // Scent increases fast at first, and slows down as it approaches normal levels.
         // Estimate it will take about norm_scent * 2 turns to go from 0 - norm_scent / 2
         // Without smelly trait this is about 1.5 hrs. Slows down significantly after that.
@@ -253,10 +258,6 @@ void Character::process_turn()
         if( scent > norm_scent ) {
             scent--;
         }
-
-        for( const trait_id &mut : get_mutations() ) {
-            scent *= mut.obj().scent_modifier;
-        }
     }
 
     // We can dodge again! Assuming we can actually move...