android: Fix unused parameter warnings on Chrome OS

The Chrome OS-specific code has multiple function parameters that are
not used. This results in compilation warnings. Fix them with
[[maybe_unused]].

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>

src/android/cros/camera3_hal.cpp

@@ -9,7 +9,7 @@
 
 #include "../camera_hal_manager.h"
 
-static void set_up(cros::CameraMojoChannelManagerToken *token)
+static void set_up([[maybe_unused]] cros::CameraMojoChannelManagerToken *token)
 {
 }