AP MLD: Do not modify flags for link stations

AP MLD: Do not modify flags for link stations

All the station flags other than WPA_STA_SHORT_PREAMBLE are relevant
only for the MLD station and not to the link stations (as these flags
are related to the MLD state and not the link state).

As for the WPA_STA_SHORT_PREAMBLE, since the station is an EHT
station, it must have short preamble.

Thus, do not propagate the flags change for link stations to the driver.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>