Camera: reduce long inflight request list spam

By checking the expected duration for all inflight requests to
finish and only log when it takes more than a threshold (5 secs)
to process all inflight requests and the list is long.

Test: manual testing
Bug: 135927862
Change-Id: Iaa2c593f1e69f63b1da7d35d73c696de3510cd2c
diff --git a/services/camera/libcameraservice/device3/Camera3Device.h b/services/camera/libcameraservice/device3/Camera3Device.h
index 6e8ac84..cae34ce 100644
--- a/services/camera/libcameraservice/device3/Camera3Device.h
+++ b/services/camera/libcameraservice/device3/Camera3Device.h
@@ -227,6 +227,7 @@
     static const size_t        kDumpLockAttempts  = 10;
     static const size_t        kDumpSleepDuration = 100000; // 0.10 sec
     static const nsecs_t       kActiveTimeout     = 500000000;  // 500 ms
+    static const nsecs_t       kMinWarnInflightDuration = 5000000000; // 5 s
     static const size_t        kInFlightWarnLimit = 30;
     static const size_t        kInFlightWarnLimitHighSpeed = 256; // batch size 32 * pipe depth 8
     static const nsecs_t       kDefaultExpectedDuration = 100000000; // 100 ms