wifi: cfg80211: add statistics for providing overview for MLO station

wifi: cfg80211: add statistics for providing overview for MLO station

Currently statistics are handled at link level for multi-link
operation(MLO). There is no provision to check accumulated statistics
for a multi-link(ML) station. Other statistics, such as signal, rates,
are also managed at the link level only.

Statistics such as packets, bytes, signal, rates, etc are useful to
provide overall overview for the ML stations.

Statistics such as packets, bytes are accumulated statistics at MLO level.
However, MLO statistics for rates and signal can not be accumulated since
it won't make much sense. Hence, handle other statistics such as signal,
rates, etc bit differently at MLO level.

The signal could be the best of all links-
e.g. if Link 1 has a signal strength of -70 dBm and Link 2 has -65 dBm,
the signal for MLO will be -65 dBm.

The rate could be determined based on the most recently updated link-
e.g. if link 1 has a rate of 300 Mbps and link 2 has a rate of 450 Mbps,
the MLO rate can be calculated based on the inactivity of each link.
If the inactive time for link 1 is 20 seconds and for link 2 is 10 seconds,
the MLO rate will be the most recently updated rate, which is link 2's
rate of 450 Mbps.

The inactive time, dtim_period and beacon_interval can be taken as the
least value of field from link level.

Similarly, other MLO level applicable fields are handled and the fields
which don't make much sense at MLO level, a subsequent change will handle
to embed NL message.

Hence, add accumulated and other statistics for MLO station if valid links
are present to represent comprehensive overview for the ML stations.

Signed-off-by: Sarika Sharma <quic_sarishar@quicinc.com>
Link: https://patch.msgid.link/20250528054420.3050133-5-quic_sarishar@quicinc.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>