Fix crash issue that occurred when disabling BT during scanning

Fix crash issue that occurred when disabling BT during scanning

All timeout callbacks for scan results should be removed.

0: 0x0000007f9da8bb5c in __bt_hal_send_le_scan_result_event (adv_info=adv_info@entry=0x55a81a9240)
   at /usr/src/debug/bluetooth-frwk-0.7.0-1.aarch64/bt-oal/bluez_hal/src/bt-hal-gatt.c:465 --> bluetooth-frwk-oal (rpm)
1: 0x0000007f9da8bbcc in __bt_hal_adv_scan_req_timeout_cb (user_data=0x55a81a9240, user_data@entry=<error reading variable: value has been optimized out>)
   at /usr/src/debug/bluetooth-frwk-0.7.0-1.aarch64/bt-oal/bluez_hal/src/bt-hal-gatt.c:756 --> bluetooth-frwk-oal (rpm)

Change-Id: Ifc8d42a31f6d70687423abe43335165edea62726
Signed-off-by: Wootak Jung <wootak.jung@samsung.com>