ffmpeg compile with nvidia acceleration failed

I have today updated Slackware64-current.
HP ZBook with Nvidia P2000
Installed:
nv-codec-headers-12.0.16.0-x86_64
nvidia-driver-535.113.01_multilib-x86_64
nvidia-kernel-535.113.01_6.4.16-x86_64

Nvidia krenel/driver test:
Code:__NV_PRIME_RENDER_OFFLOAD=1 __GLX_VENDOR_LIBRARY_NAME=nvidia glxinfo | grep OpenGL
OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: Quadro P2000/PCIe/SSE2
OpenGL core profile version string: 4.6.0 NVIDIA 535.113.01
OpenGL core profile shading language version string: 4.60 NVIDIA
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.6.0 NVIDIA 535.113.01
OpenGL shading language version string: 4.60 NVIDIA
OpenGL context flags: (none)
OpenGL profile mask: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.2 NVIDIA 535.113.01
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.20Code:ls -la /usr/include/ffnvcodec/
total 476
drwxr-xr-x 2 root root 4096 23.09.2023 09:46:50 .
drwxr-xr-x 603 root root 36864 28.09.2023 08:33:13 ..
-rw-r--r-- 1 root root 21876 23.09.2023 09:46:50 dynlink_cuda.h
-rw-r--r-- 1 root root 66364 23.09.2023 09:46:50 dynlink_cuviddec.h
-rw-r--r-- 1 root root 22503 23.09.2023 09:46:50 dynlink_loader.h
-rw-r--r-- 1 root root 28494 23.09.2023 09:46:50 dynlink_nvcuvid.h
-rw-r--r-- 1 root root 291178 23.09.2023 09:46:50 nvEncodeAPI.hcompiling ffmpeg from slackware source or Aliens repository-restricted both do not compile nvidia hardware acclerated encoders. There are no nvenc encoders:
Code:ffmpeg -hide_banner -encoders |grep H.26
V..... flv FLV / Sorenson Spark / Sorenson H.263 (Flash Video) (codec flv1)
V..... h261 H.261
V..... h263 H.263 / H.263-1996
V..... h263_v4l2m2m V4L2 mem2mem H.263 encoder wrapper (codec h263)
V.S... h263p H.263+ / H.263-1998 / H.263 version 2
V....D libx264 libx264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (codec h264)
V....D libx264rgb libx264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 RGB (codec h264)
V..... h264_qsv H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (Intel Quick Sync Video acceleration) (codec h264)
V..... h264_v4l2m2m V4L2 mem2mem H.264 encoder wrapper (codec h264)
V....D h264_vaapi H.264/AVC (VAAPI) (codec h264)
V....D libx265 libx265 H.265 / HEVC (codec hevc)
V....D hevc_vaapi H.265/HEVC (VAAPI) (codec hevc)Looks like autodetection of nv codec headers do not detect them, or something else is missing.
As a result ffmpeg is not nvidia accelerated.:(

Please help.