Offload Visualizer CAPTURE_DEVICE changed on tavil (wahoo)

The offload effect capture card has always been the nb 8 before
wahoo devices.
This value 8 was hard-coded in the offload visualizer even though
on Wahoo the correct value is 7.

The proper fix would be to link with the hal to retrieve the correct
value depending on the platform configuration.
Nevertheless there is no time for MR1 for this proper fix.
This hack will be reverted in master as soon as qcom provides the fix.

Bug: 64373855
Bug: 65026253
Bug: 65263761
Test: enabled visualizer on mp3 music (play music) in test app
Change-Id: I2036f694a6028c637582e55aa71ef56b4fa9d328
Signed-off-by: Kevin Rocard <krocard@google.com>