wifi: mac80211: make VHT opmode NSS ignore a debug message

There's no need to always print it, it's only useful for
debugging specific client issues. Make it a debug message.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Link: https://lore.kernel.org/linux-wireless/20250529070922.3467-1-pmenzel@molgen.mpg.de/
Link: https://patch.msgid.link/20250708105849.22448-2-johannes@sipsolutions.net


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