apps: cam: Print control array sizes

Now that controls can be queried for array information, print it in
--list-controls when applicable.

Example output (with dummy controls added to vimc):

$ cam -c 1 --list-controls
Using camera platform/vimc.0 Sensor B as cam0
Control: ColourGains: [1.000000..4.000000]
   Size: 2
Control: Brightness: [-1.000000..1.000000]
Control: AfWindows: [(0, 0)/1x1..(0, 0)/100x100]
   Size: n
Control: Contrast: [0.000000..2.000000]
Control: Saturation: [0.000000..2.000000]

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

src/apps/cam/camera_session.cpp

@@ -176,6 +176,17 @@ void CameraSession::listControls() const
 				std::cout << " (" << val << ")" << std::endl;
 			}
 		}
+
+		if (id->isArray()) {
+			std::size_t size = id->size();
+
+			std::cout << "   Size: ";
+			if (size == std::numeric_limits<std::size_t>::max())
+				std::cout << "n";
+			else
+				std::cout << std::to_string(size);
+			std::cout << std::endl;
+		}
 	}
 }