Do not disable 40 MHz based on co-ex report with matching primary channel

Do not disable 40 MHz based on co-ex report with matching primary channel

When processing 20/40 BSS Coexistence Management frames that do not
explicitly require 40 MHz to be disabled, check whether the reported
channels in 20/40 BSS Intolerant Channel Report element match the
current primary channel. If so, allow 40 MHz operation to continue. This
makes the during-operation updates for 20/40 Operation Permitted more
consistent with the scans during initial BSS startup.

The received 20/40 BSS Intolerant Channel Report channels are to be used
in the OT set in the during-operation determination and the P == OT_i
exception was ignored in the previous implementation which could result
in the AP first starting with 40 MHz and then dropping to 20 MHz on
first received 20/40 BSS Coexistence Management frame even though there
was no change in the neighboring BSSs.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>