configs: specify dedicated tx path for SVA

Allocate dedicated tx path for SVA:
    SLIM ports: 0, 1, 2, 3
    Backend: SLIM_1_TX
This is to allow concurrency with audio recording which uses:
    SLIM ports: 5, 6, 7, 8
    Backend: SLIM_0_TX

Change-Id: If8bc2724c73f7f3b350ec5c975c3d898bf95a103