gpu: nvgpu: remove "trace/events/gk20a.h" from QNX build

- "include/trace/events/gk20a.h" file was having GPL2 license
(which should not used for QNX code). This file was used for
compiling linux userspace driver("libnvgpu-drv.so") and was used for
unit testing on QNX.
- This patch removes stubs in "include/trace/events/gk20a.h" file.
(which were used for linux userspace driver.)
- For QNX driver, "nvgpu_rmos/trace/events/gk20a.h" was used.
This patch moves that file to "include/nvgpu/posix/trace_gk20a.h" and
does relevant license change. This same file will be used for linux
userspace driver.
- This patch also creates a new file "include/nvgpu/trace.h" which
selects proper trace file depending on the config.

Bug 2802414

Change-Id: Icdfb251e5698073f986753a969e804161af3ecc5
Signed-off-by: Vaibhav Kachore <vkachore@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2286388
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/os/linux/linux-channel.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019, NVIDIA Corporation.  All rights reserved.
+ * Copyright (c) 2017-2020, NVIDIA Corporation.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -38,9 +38,7 @@
 
 #include <linux/uaccess.h>
 #include <linux/dma-buf.h>
-#ifdef CONFIG_NVGPU_TRACE
-#include <trace/events/gk20a.h>
-#endif
+#include <nvgpu/trace.h>
 #include <uapi/linux/nvgpu.h>
 
 #include "sync_sema_android.h"