android: CameraHalManager: Create a static object dynamically

Originally CameraHalManager is created in the libcamera start up
and destroyed in the libcamera termination. However,
CameraHalManager destructor can access  other static objects that
has been destroyed.
Avoid this issue by destroying CameraHalManager when tear_down() is
called in ChromeOS or leaking it in other platforms.

Signed-off-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/android/camera_hal_manager.h

@@ -26,9 +26,10 @@ class CameraDevice;
 class CameraHalManager
 {
 public:
-	CameraHalManager();
 	~CameraHalManager();
 
+	static CameraHalManager *instance();
+
 	int init();
 
 	std::tuple<CameraDevice *, int>
@@ -44,6 +45,8 @@ private:
 
 	static constexpr unsigned int firstExternalCameraId_ = 1000;
 
+	CameraHalManager();
+
 	static int32_t cameraLocation(const libcamera::Camera *cam);
 
 	void cameraAdded(std::shared_ptr<libcamera::Camera> cam);