Examples ep: cosmetic changes to new SYCL implementations

[stepas-toliautas]

Just a little code-polish to make files look as similar as possible to reference source code on screen (f. e. in episode code tabs).

[ashwinvis]

May be you meant this too, but I felt it would be nice if we:

1. add the file name in the tab title / starting of the source code, and / or
2. rename such that the file name matches the tab titles.

For example, just by looking here, I could not figure out which is the source code file:

[ashwinvis]

It goes without saying that all other code tabs had the same problem.