qtnfmac: add missing bss record to host scan cache

Make sure that valid BSS entry exists in wireless core record
even in the case of successful connect reported by firmware.

Signed-off-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>