wifi: mac80211: allow bw change during channel switch in mesh

[ Upstream commit 6b75f133fe05c36c52d691ff21545d5757fff721 ]

From 'IEEE Std 802.11-2020 section 11.8.8.4.1':
  The mesh channel switch may be triggered by the need to avoid
  interference to a detected radar signal, or to reassign mesh STA
  channels to ensure the MBSS connectivity.

  A 20/40 MHz MBSS may be changed to a 20 MHz MBSS and a 20 MHz
  MBSS may be changed to a 20/40 MHz MBSS.

Since the standard allows the change of bandwidth during
the channel switch in mesh, remove the bandwidth check present in
ieee80211_set_csa_beacon.

Fixes: c6da674a ("{nl,cfg,mac}80211: enable the triggering of CSA frame in mesh")
Signed-off-by: Hari Chandrakanthan <quic_haric@quicinc.com>
Link: https://lore.kernel.org/r/1658903549-21218-1-git-send-email-quic_haric@quicinc.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>