libcamera: PixelFormat: Mark all function arguments of type PixelFormat as const reference

PixelFormat was previously an alias for unsigned int but is now a
class. Make all functions taking PixelFormat do so as a const reference.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/qcam/format_converter.cpp

@@ -25,8 +25,8 @@
 #define CLIP(x)			CLAMP(x,0,255)
 #endif
 
-int FormatConverter::configure(libcamera::PixelFormat format, unsigned int width,
-			       unsigned int height)
+int FormatConverter::configure(const libcamera::PixelFormat &format,
+			       unsigned int width, unsigned int height)
 {
 	switch (format) {
 	case DRM_FORMAT_NV12: