libcamera: stream: Add StillCaptureRaw role

Add a role for capturing high resolution, low frame rate, still images
in RAW format.

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

include/libcamera/stream.h

@@ -58,6 +58,7 @@ private:
 
 enum StreamRole {
 	StillCapture,
+	StillCaptureRaw,
 	VideoRecording,
 	Viewfinder,
 };

src/libcamera/stream.cpp

@@ -361,6 +361,9 @@ std::string StreamConfiguration::toString() const
  * \var StillCapture
  * The stream is intended to capture high-resolution, high-quality still images
  * with low frame rate. The captured frames may be exposed with flash.
+ * \var StillCaptureRaw
+ * The stream is intended to capture high-resolution, raw still images with low
+ * frame rate.
  * \var VideoRecording
  * The stream is intended to capture video for the purpose of recording or
  * streaming. The video stream may produce a high frame rate and may be