ffmpeg: Update to version 7.1

ffmpeg: Update to version 7.1

- Update from version 7.0.2 to 7.1
- Update of rootfile
- Changelog
    7.1
	- Raw Captions with Time (RCWT) closed caption demuxer
	- LC3/LC3plus decoding/encoding using external library liblc3
	- ffmpeg CLI filtergraph chaining
	- LC3/LC3plus demuxer and muxer
	- pad_vaapi, drawbox_vaapi filters
	- vf_scale supports secondary ref input and framesync options
	- vf_scale2ref deprecated
	- qsv_params option added for QSV encoders
	- VVC decoder compatible with DVB test content
	- xHE-AAC decoder
	- removed DEC Alpha DSP and support code
	- VVC encoding support via libvvenc
	- perlin video source
	- D3D12VA HEVC encoder
	- Cropping metadata parsing and writing in Matroska and MP4/MOV de/muxers
	- Intel QSV-accelerated VVC decoding
	- MediaCodec AAC/AMR-NB/AMR-WB/MP3 decoding
	- YUV colorspace negotiation for codecs and filters, obsoleting the
	  YUVJ pixel format
	- Vulkan H.264 encoder
	- Vulkan H.265 encoder
	- stream specifiers in fftools can now match by stream disposition
	- LCEVC enhancement data exporting in H.26x and MP4/ISOBMFF
	- LCEVC filter
	- MV-HEVC decoding

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>