qcam: viewfinder: Use PixelFormat default constructor

There's no need to initialize the PixelFormat stored in ViewFinder
explicitly, as PixelFormat is now a class with a default constructor.
Remove the initialization.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/qcam/viewfinder.cpp

@@ -16,7 +16,7 @@
 #include "format_converter.h"
 
 ViewFinder::ViewFinder(QWidget *parent)
-	: QWidget(parent), format_(0)
+	: QWidget(parent)
 {
 }