Bluetooth: Tester: Adjust bap ext adv options

This change removes the BT_LE_PER_ADV_OPT_USE_TX_POWER option for
extended advertisement in BLE Audio PTS tests.

The Broadcaster setup options was hardcoded to include the
BT_LE_PER_ADV_OPT_USE_TX_POWER option. This causes incompabilities
for any controller not support it, and since the option is not
required for the audio tests it should not be used here.

signed-off-by: Frode van der Meeren <frode.vandermeeren@nordicsemi.no>