DOC: Remove makePanel from docs (#25609)
- [x] closes #25609
- [ ] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

As described in #25609, I removed the tm.makePanel() calls from the docs, along with some of the surrounding sections (a few "Deprecate Panel" sections).  I did not replace these calls with an equivalent manual creation of a Panel.

If desired, I could create a panel manually in the docs with something like this:

```
cols = ['Item' + c for c in string.ascii_uppercase[:K - 1]]	
data = {c: tm.makeTimeDataFrame() for c in cols}	
p = Panel.fromDict(data)
```

but this PR is currently as requested in the issue with the sections removed.