[AdaptiveStream] Commented out code to unknown range on SIDX

[CastagnaIT]

Description

i have no memories of this, it was introduced many years ago on branch leia https://github.com/xbmc/inputstream.adaptive/blob/de8c1d6072b9326b23b81e4512f2b41d894d005f/src/parser/DASHTree.cpp#L1269-L1277

for not so clear use with DASH subtitles (because in the past the handling of subtitles cases was very messy...) even reading again the DASH specifications, i could not find an appropriate use for this "unknown" data range case

if anyone knows the use case and possibility a test stream, please leave a comment

for now i see no reason to keep unclear code, commented for future removal

How has this been tested?

tested various streams with subs, not found any use of this code on my samples

Screenshots (if appropriate):

Types of change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] Clean up (non-breaking change which removes non-working, unmaintained functionality)
• [ ] Improvement (non-breaking change which improves existing functionality)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Breaking change (fix or feature that will cause existing functionality to change)
• [ ] Cosmetic change (non-breaking change that doesn't touch code)
• [ ] None of the above (please explain below)

Checklist:

• [ ] I have read the Contributing document
• [ ] My code follows the Code Guidelines of this project
• [ ] My change requires a change to the Wiki documentation
• [ ] I have updated the documentation accordingly