ath6kl: Fix 4-way handshake failure in AP and P2P GO mode

RSN capability field of RSN IE which is generated (which is what really
advertised in beacon/probe response) differs from the one generated in
wpa_supplicant. This inconsistency in rsn IE results in 4-way handshake
failure. To fix this, configure rsn capability used in wpa_supplicant
in firmware using a new wmi command, WMI_SET_IE_CMDID. There is a bit
(ATH6KL_FW_CAPABILITY_RSN_CAP_OVERRIDE) in fw_capabilities to advertise
this support to driver.

Signed-off-by: Subramania Sharma <sharmat@qca.qualcomm.com>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>