Fix vts sco test fail for usb interface

[Description]
If bt controller device is usb interface,
sco loopback single pkt and bandwidth test can not pass
because pkt size is limited accroding to core spec

[Root Cause]
USB sco packet size is limited in spec

[Solution]
If is bt usb chip, continuous receive sco packets
  from controller until size is enough

[Test Report]
Test Pass

Bug: 286355871
Change-Id: Idb150d8a72149f7e1dfaccfd7bc82a91710da59c