Change: Use gender-neutral pronouns

src/ship_cmd.cpp

@@ -257,7 +257,7 @@ Trackdir Ship::GetVehicleTrackdir() const
 	}
 
 	if (this->state == TRACK_BIT_WORMHOLE) {
-		/* ship on aqueduct, so just use his direction and assume a diagonal track */
+		/* ship on aqueduct, so just use its direction and assume a diagonal track */
 		return DiagDirToDiagTrackdir(DirToDiagDir(this->direction));
 	}