BACKPORT: mac80211: Add HE 6GHz capabilities element to probe request

On 6 GHz, the 6 GHz capabilities element should be added, do that.

Bug: 163110886

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
[add commit message]
Link: https://lore.kernel.org/r/20200528213443.8ee764f0cde0.I2b0c66b60e11818c97c9803e04a6a197c6376243@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Change-Id: Iba5daa73817072fdea78cd37c1f30b0323deca6f
(cherry picked from commit 2ad2274c)
Signed-off-by: Vamsi Krishna <vamsin@codeaurora.org>