Various parts of libcamera print the representation of a MediaLink by
inline joining the parts to make a string representation.
This repeated use case can be supported with a common helper to print
the MediaLink in a common manner using the existing toString() and
operator<< overload style to make it easier to report on MediaLink
types.
This implementation will report in the following style:
'imx283 1-001a'[0] -> 'video-mux'[0]
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Stefan Klug <stefan.klug@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>