[Docs] Update 18.10 Release notes
[Docs] Update 18.10 Release notes

Updated release notes with current state
of release.

Resolves: LE-11491
Change-Id: I8169da48cef8e19056d46afbc9429eb075299fa7

legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af