tegra: Sync with Linux kernel UAPI header

Update the UAPI header to the latest version in the Linux kernel. This
changes the struct drm_tegra_gem_mmap to properly handle offsets on 64-
bit architectures.

See commit bdf765071a8b ("drm/tegra: gem: Return 64-bit offset for
mmap(2)") in the Linux kernel (as of v4.1).

Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
diff --git a/include/drm/tegra_drm.h b/include/drm/tegra_drm.h
index 8dae8f3..7c0fe0e 100644
--- a/include/drm/tegra_drm.h
+++ b/include/drm/tegra_drm.h
@@ -36,7 +36,8 @@
 
 struct drm_tegra_gem_mmap {
 	__u32 handle;
-	__u32 offset;
+	__u32 pad;
+	__u64 offset;
 };
 
 struct drm_tegra_syncpt_read {