wifi: iwlwifi: mvm: move RU alloc B2 placement

wifi: iwlwifi: mvm: move RU alloc B2 placement

The firmware was trying to report the B2 RU allocation in
the place previously used here as well, but there's a HW
block that clears the lower 8 bits in this metadata word
even in sniffer mode. Thus, firmware moved B2 to another
place, follow that.

There's no need to detect the version since moving it to
the other place if firmware didn't just means that we'll
continue to report the (erroneous) zero value, and it's
not really something we can detect from the firmware now.

While debugging this we realized that the comments about
placement in the metadata dwords are wrong, update them.

Reported-by: Youhan Kim <youhank@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230830112059.dec7f1e07ff8.I623fee2d710cc7b6f392d65b708883ed58632b45@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>