Fix some memory leaks.

Adjusted a unit test or two to make leaks easier to find, and then fixed
a few leaks.

Change-Id: I47a20df8de7cac113d34a2015f76a65ab957dedd
Reviewed-by: Dmytro Poplavskiy <dmytro.poplavskiy@nokia.com>

src/multimedia/camera/qcameraexposure.cpp

@@ -216,6 +216,8 @@ QCameraExposure::~QCameraExposure()
     Q_D(QCameraExposure);
     if (d->exposureControl)
         d->camera->service()->releaseControl(d->exposureControl);
+
+    delete d;
 }
 
 /*!

src/multimedia/camera/qcamerafocus.cpp

@@ -394,6 +394,7 @@ QCameraFocus::QCameraFocus(QCamera *camera):
 
 QCameraFocus::~QCameraFocus()
 {
+    delete d_ptr;
 }
 
 /*!

src/multimedia/camera/qcameraimagecapture.cpp

@@ -178,6 +178,8 @@ QCameraImageCapture::~QCameraImageCapture()
 
     if (d->mediaObject)
         d->mediaObject->unbind(this);
+
+    delete d_ptr;
 }
 
 /*!

src/multimedia/camera/qcameraimageprocessing.cpp

@@ -162,6 +162,7 @@ QCameraImageProcessing::QCameraImageProcessing(QCamera *camera):
 
 QCameraImageProcessing::~QCameraImageProcessing()
 {
+    delete d_ptr;
 }