Add usb audio device warning dialog message strings

for support both Direct USB Access and AoC Offload feature

Add below new string IDs for USB audio device warning dialog message:
usb_audio_device_prompt_warn
usb_audio_device_prompt
usb_audio_device_confirm_prompt_title
usb_audio_device_permission_prompt_title

Bug: 199034378

Test: Passed in local build.
Change-Id: Ib64526e6e6a7344ff1138ee1932629a4c221fd4a
(cherry picked from commit e159881f)