android, controls: Add and plumb MaxLatency control

Add a MaxLatency control, and plumb it into the HAL accordingly.

Bug: https://bugs.libcamera.org/show_bug.cgi?id=50
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

src/libcamera/control_ids.yaml

@@ -622,6 +622,16 @@ controls:
         detection, additional format conversions etc) count as an additional
         pipeline stage.
 
+  - MaxLatency:
+      type: int32_t
+      draft: true
+      description: |
+        The maximum number of frames that can occur after a request (different
+        than the previous) has been submitted, and before the result's state
+        becomes synchronized. A value of -1 indicates unknown latency, and 0
+        indicates per-frame control. Currently identical to
+        ANDROID_SYNC_MAX_LATENCY.
+
   - TestPatternMode:
       type: int32_t
       draft: true