[ffmpeg hevc] Build require amd gpu

[jeremie bergeron]

With ffmpeg 8.0.1-4, if I run the command: ffprobe hdr10tags-stream.mp4, I
get this error:
[AMF @ 0xa00056680] DLL amfrt64.dll failed to open
[hevc_amf @ 0xa00053800] Failed to create  hardware device context (AMF) :
Unknown error occurred
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xa0004ca40] Failed to open codec in
avformat_find_stream_info
[AMF @ 0xa00056a40] DLL amfrt64.dll failed to open
[hevc_amf @ 0xa00053800] Failed to create  hardware device context (AMF) :
Unknown error occurred

It is pretty normal that it fails since I don't have an amd gpu, so I
don't have the amfrt64 dll.

Note that any hevc file will produce this error. hdr10tags-stream.mp4 is
available here:
https://storage.googleapis.com/ffms2tests/hdr10tags-stream.mp4

Would it be possible to disable this hardware decoder?