Change the return type of the 2Data functions to size_t

[kevinbackhouse]

The 2Data functions (us2Data, ul2Data, ...) return the number of bytes written, so size_t is more appropriate than long.

[codecov]

Codecov Report

Merging #2281 (9430067) into main (39239ce) will increase coverage by 0.01%.
The diff coverage is 95.45%.

@@            Coverage Diff             @@
##             main    #2281      +/-   ##
==========================================
+ Coverage   63.52%   63.53%   +0.01%     
==========================================
  Files         118      118              
  Lines       19604    19595       -9     
  Branches     9584     9576       -8     
==========================================
- Hits        12453    12450       -3     
+ Misses       5086     5079       -7     
- Partials     2065     2066       +1     

Impacted Files	Coverage Δ
include/exiv2/types.hpp	76.59% <ø> (ø)
src/tiffcomposite_int.cpp	75.60% <66.66%> (-0.33%)	⬇️
include/exiv2/value.hpp	84.51% <100.00%> (ø)
src/types.cpp	94.47% <100.00%> (ø)
src/xmpsidecar.cpp	64.28% <0.00%> (-0.37%)	⬇️
app/exiv2.cpp	62.48% <0.00%> (-0.20%)	⬇️
src/jp2image.cpp	70.19% <0.00%> (-0.07%)	⬇️
src/tiffvisitor_int.cpp	79.45% <0.00%> (-0.03%)	⬇️
src/casiomn_int.cpp	6.89% <0.00%> (ø)
... and 6 more

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[piponazo]

LGTM

Pull request has been modified.