kmd: re-enable the panic_callback

- introduced a panic_flag in the tegra_rtcpu_trace.
- set panic_flag to 1 when kmd receives panic hsp
  message from RCE.
- the trace buffer readout thread calls rtcpu_trace_snapshot
  to dump out the snapshot section when panic_flag is set to 1.

Bug 5293085

Change-Id: Ief5d9431bfc944fc588f38a69f7758f829cf2e6e
Signed-off-by: yizhou <yizhou@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3368252
Reviewed-by: Evgeny Kornev <ekornev@nvidia.com>
GVS: buildbot_gerritrpt <buildbot_gerritrpt@nvidia.com>
Reviewed-by: Chinniah Poosapadi <cpoosapadi@nvidia.com>
Reviewed-by: Mohit Ingale <mohiti@nvidia.com>
Reviewed-by: Kalle Jokiniemi <kjokiniemi@nvidia.com>

drivers/platform/tegra/rtcpu/tegra-camera-rtcpu-base.c

@@ -1316,7 +1316,8 @@ void rtcpu_trace_panic_callback(struct device *dev)
 		return;
 	}
 
-	rtcpu_trace_snapshot(tracer);
+	/* Call the accessor function to set panic flag */
+	tegra_rtcpu_trace_set_panic_flag(tracer);
 }
 EXPORT_SYMBOL(rtcpu_trace_panic_callback);