host/ble_gap.c: Fix failure to run callback on finished scan
host/ble_gap.c: Fix failure to run callback on finished scan

When both roles - peripheral and central where turned off, removed lines where causing
not calling callback function after completing the scan.

apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble