[PATCH] Documentation: real-time/index: add entry

[Manuel Ebner]

I figured out the subject and changelog aren't good. It should be:

[PATCH] Documentation: real-time/index: add entry

Add reference to realtime/index.rst pointing to scheduler/sched-rt-group.rst

Signed-off-by: Manuel Ebner <manuelebner@xxxxxxxxxxx>
---

I'm waiting for feedback before making [v2].

Thanks 
 Manuel