configs: sdm845: Fix mixer path names for VoIP playback

For VoIP playback usecase, mixer path names referenced in xml file
for USB_RX and SCO_RX did not match with routing definitions. Hence,
backend was not connected resulting in audio loss. This change
fixes the names referenced in xml file.

Change-Id: Ib1a03dd7a67f3ecc0ac78b4c7c2cdfcaed1cb557