mac80211: improve AP disconnect message

If the AP changes capability/bandwidth in some fashion, the
message might be somewhat misleading and we don't know what
really changed. Modify the message to speak about "caps/bw"
instead of just "bandwidth", and print out the flags.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210618133832.dc22c48985fa.I4bf5fbc17ec783c21d4b50c8c35b1de390896ccd@changeid


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