mac80211: Unsolicited broadcast probe response support

This patch adds mac80211 support to configure unsolicited
broadcast probe response transmission for in-band discovery in 6GHz.

Changes include functions to store and retrieve probe response template,
and packet interval (0 - 20 TUs).
Setting interval to 0 disables the unsolicited broadcast probe response
transmission.

Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
Link: https://lore.kernel.org/r/010101747a946b35-ad25858a-1f1f-48df-909e-dc7bf26d9169-000000@us-west-2.amazonses.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>