Add audio software document design
Add audio software document design

Resolves: LE-3777
Change-Id: I1daaa4e1039549ffcf51aaa7ffb32878ac6d0287

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