qtnfmac: validate interface combinations on changes

qtnfmac: validate interface combinations on changes

Validate new interface combinations using wireless core checks when new
interface is added or when the type of existing interface is modified.
This is performed to make sure that new interface combination is supported
by hardware. As a result, invalid interface combinations are rejected early,
rather than passed to hardware with sometimes unpredictable results.

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