Fix invalid stepheight increase calculation on android

src/localplayer.cpp

@@ -209,7 +209,7 @@ void LocalPlayer::move(f32 dtime, Environment *env, f32 pos_max_d,
 	float player_stepheight = touching_ground ? (BS*0.6) : (BS*0.2);
 
 #ifdef __ANDROID__
-	player_stepheight += 0.5;
+	player_stepheight += (0.5 * BS);
 #endif
 
 	v3f accel_f = v3f(0,0,0);