Remove never-set vars tBTM_CB::tBTM_BLE_CB::tBTM_BLE_INQ_CB::

tBTM_CB::tBTM_BLE_CB::tBTM_BLE_INQ_CB::adv_interval_min
tBTM_CB::tBTM_BLE_CB::tBTM_BLE_INQ_CB::adv_interval_max

Towards readable code

Bug: 163134718
Tag: #refactor
Test: acts -tc BleCocTest
Test: ble paired 2 phones

Change-Id: I263e4cfd19a17affd9838cbaad52abb3fbe4185b