(q)cam: Fix header guards

Several headers belonging to cam and qcam use __LIBCAMERA_*_H__ as a
header guard. They're not part of the libcamera core, use __CAM_*_H__
and __QCAM_*_H__ instead, similarly to all other headers of cam and
qcam.

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

src/qcam/dng_writer.h

@@ -4,8 +4,8 @@
  *
  * dng_writer.h - DNG writer
  */
-#ifndef __LIBCAMERA_DNG_WRITER_H__
-#define __LIBCAMERA_DNG_WRITER_H__
+#ifndef __QCAM_DNG_WRITER_H__
+#define __QCAM_DNG_WRITER_H__
 
 #ifdef HAVE_TIFF
 #define HAVE_DNG
@@ -28,4 +28,4 @@ public:
 
 #endif /* HAVE_TIFF */
 
-#endif /* __LIBCAMERA_DNG_WRITER_H__ */
+#endif /* __QCAM_DNG_WRITER_H__ */