Retain the Encoded Library information stored in a tag (fix #1267)

[eugenesvk]

This fixes #1267

[eugenesvk]

I see that this Travis CI job failed with ../.libs/libmediainfo.so: undefined reference to 'MediaInfoLib::Encoded_Library_Tag' error and with these options seemingly different from a successfull build

-DMEDIAINFO_ALL_NO -DMEDIAINFO_MIXML_YES"
$ export RUN_TESTS="mixml"

Not sure what these are and how I can turn them on on my side to test (I was only using the MSVC2019 project), so will wait for your input

[JeromeMartinez]

@eugenesvk thanks for the PR. I don't want to have more source file for this unique item, I'll adapt your patch proposal.

[eugenesvk]

That's totally fine, it was just the simplest way I found to fix it (I was also thinking of disabling the split into name/version as at first glance it only seemed to be useful to remove a "-" in "x265 - ..." :), but then it was more complicated to trying to figure out all of its uses