Update includes to L4T r32.7.4 and drop nvgpu/gk20a.h dependency

Also add instructions for updating `include/`. These files are now
only needed to build on Linux 4.9-based Tegra platforms.

1 files changed, 2 insertions, 2 deletions

diff --git a/include/os/linux/debug.c b/include/os/linux/debug.c
index 5f0703c..b8c4596 100644
--- a/include/os/linux/debug.c
+++ b/include/os/linux/debug.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2017-2018 NVIDIA Corporation.  All rights reserved.
+ * Copyright (C) 2017-2021 NVIDIA Corporation.  All rights reserved.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
@@ -224,7 +224,7 @@ static int railgate_residency_show(struct seq_file *s, void *data)
         unsigned long total_rail_gate_time_ms;
         unsigned long total_rail_ungate_time_ms;
 
-        if (platform->is_railgated(dev_from_gk20a(g))) {
+        if (platform && platform->is_railgated && platform->is_railgated(dev_from_gk20a(g))) {
                 time_since_last_state_transition_ms =
                                 jiffies_to_msecs(jiffies -
                                 g->pstats.last_rail_gate_complete);