Add SonyMisc3c makernote tags (tag 9400)

[postscript-dev]

Changes:

• Add tags. Rename Exiftool's SequenceLength tags to SequenceLength1
  and SequenceLength2, to prevent a name clash
• Update docs and manpage
• Add testing, including 2 EXV files extracted from Exiftool's Sony image
  samples (https://exiftool.org/sample_images.html)

Source: Exiftool

[codecov]

Codecov Report

Merging #1800 (a82b6ce) into main (c474277) will increase coverage by 0.33%.
The diff coverage is 67.05%.

@@            Coverage Diff             @@
##             main    #1800      +/-   ##
==========================================
+ Coverage   67.52%   67.85%   +0.33%     
==========================================
  Files         151      151              
  Lines       20901    20932      +31     
==========================================
+ Hits        14113    14204      +91     
+ Misses       6788     6728      -60     

Impacted Files	Coverage Δ
src/makernote_int.hpp	91.66% <ø> (ø)
src/tags_int.cpp	87.20% <ø> (ø)
src/tags_int.hpp	90.90% <ø> (ø)
src/tiffimage_int.cpp	89.28% <ø> (ø)
src/sonymn_int.cpp	68.98% <62.66%> (-4.24%)	⬇️
src/makernote_int.cpp	80.52% <100.00%> (+0.47%)	⬆️
src/iptc.cpp	75.72% <0.00%> (-0.34%)	⬇️
src/version.cpp	91.51% <0.00%> (-0.21%)	⬇️
src/image.cpp	72.74% <0.00%> (-0.17%)	⬇️
src/exiv2app.hpp	100.00% <0.00%> (ø)
... and 12 more

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[postscript-dev]

Thanks @kevinbackhouse for looking at this and the other PRs that you have checked.

[kevinbackhouse]

@postscript-dev: No problem! Just be aware that I know absolutely nothing about cameras! I'm just checking that the C++ looks correct.