ath11k: reset RSN/WPA present state for open BSS

The ath11k driver is caching the information about RSN/WPA IE in the
configured beacon template. The cached information is used during
associations to figure out whether 4-way PKT/2-way GTK peer flags need to
be set or not.

But the code never cleared the state when no such IE was found. This can
for example happen when moving from an WPA/RSN to an open setup. The
(seemingly connected) peer was then not able to communicate over the
link because the firmware assumed a different (encryption enabled) state
for the peer.

Tested-on: IPQ6018 hw1.0 AHB WLAN.HK.2.5.0.1-01100-QCAHKSWPL_SILICONZ-1

Fixes: 01e34233 ("ath11k: fix wmi peer flags in peer assoc command")
Cc: Venkateswara Naralasetty <vnaralas@codeaurora.org>
Reported-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Karthikeyan Kathirvel <kathirve@codeaurora.org>
[sven@narfation.org: split into separate patches, clean up commit message]
Signed-off-by: Sven Eckelmann <sven@narfation.org>

Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211115100441.33771-2-sven@narfation.org