wifi: mt76: mt7925: fix the wrong bss cleanup for SAP

When in SAP mode, if a STA disconnect, the SAP's BSS
should not be cleared.

Fixes: 0ebb60da ("wifi: mt76: mt7925: adjust rm BSS flow to prevent next connection failure")
Cc: stable@vger.kernel.org
Signed-off-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Link: https://patch.msgid.link/20250728052612.39751-1-mingyen.hsieh@mediatek.com


Signed-off-by: Felix Fietkau <nbd@nbd.name>