cfg80211: Add support to calculate and report 4096-QAM HE rates

Drivers supporting 4096-QAM rates as a vendor extension in HE mode need
to update the correct rate info to userspace while using 4096-QAM (MCS12
and MCS13) in HE mode. Add support to calculate bitrates of HE-MCS12 and
HE-MCS13 which represent the 4096-QAM modulation schemes. The MCS12 and
MCS13 bitrates are defined in IEEE P802.11be/D0.1.

In addition, scale up the bitrates by 3*2048 in order to accommodate
calculations for the new MCS12 and MCS13 rates without losing fraction
values.

CRs-Fixed: 2796770
Signed-off-by: Vamsi Krishna <vamsin@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Link: https://lore.kernel.org/r/20201029183457.7005-1-jouni@codeaurora.org


Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Git-commit: 9c97c88d2f4b221d99491c3196da42004c195fb5
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next.git


Change-Id: I44f71f40a57b57703bbbe138e690d6f92369d0ec
Signed-off-by: Vamsi Krishna <vamsin@codeaurora.org>