Add support for DTMF redirection to USB interface
Add support for DTMF redirection to USB interface

Resolves: LE-6827
Change-Id: I6220b512490af5d9258ae537aa8f21ed425a74d9

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