hal: APQ8084 uses AUDIO_PARAMETER_KEY_BT_SCO_WB for bluetooth wideband

MSM8974 CAF hal uses it's own AUDIO_PARAMETER_KEY_BTSCO to setup bluetooth
wideband, while APQ8084 uses standard AUDIO_PARAMETER_KEY_BT_SCO_WB from
libhardware. Add a ifdef clause to handle properly both MSM8974 and APQ8084.

Change-Id: If1bd4ab1468aa532e3f5a9674680fd7246653413
(cherry picked from commit 506b1e16)