v3.2.2: improved fullscreen option eligibility on Android

ios/src/main/java/com/shatteredpixel/shatteredpixeldungeon/ios/IOSPlatformSupport.java

@@ -67,6 +67,12 @@ public class IOSPlatformSupport extends PlatformSupport {
 		Gdx.gl.glViewport(0, Game.bottomInset, Game.width, Game.height);
 	}
 
+	@Override
+	public boolean supportsFullScreen() {
+		//iOS supports hiding UI via drawing into the gesture safe area
+		return Gdx.graphics.getSafeInsetBottom() > 0;
+	}
+
 	@Override
 	public void updateSystemUI() {
 		int prevInset = Game.bottomInset;