Android not connecting to RasPi access point

[dr.n]

- everything connects to the access point except android devices
- see also https://raspberrypi.stackexchange.com/questions/107188/android-wont-connect-to-raspi-access-point

- can be resolved by upgrading wpa supplicant to v2.9 (building it manually) using this .config:

CONFIG_TLS=internal
CONFIG_INTERNAL_LIBTOMMATH=y
CONFIG_INTERNAL_LIBTOMMATH_FAST=y
CONFIG_IEEE8021X_EAPOL=y
CONFIG_ERP=y
CONFIG_EAP_MD5=y
CONFIG_MSCHAPV2=y
CONFIG_EAP_TLS=y
CONFIG_EAP_PEAP=y
CONFIG_EAP_TTLS=y
CONFIG_EAP_GTC=y
CONFIG_EAP_OTP=y
CONFIG_EAP_PSK=y
CONFIG_EAP_PAX=y
CONFIG_EAP_LEAP=y
CONFIG_EAP_SIM=y
CONFIG_EAP_AKA=y
CONFIG_EAP_AKA_PRIME=y
CONFIG_EAP_VENDOR_TEST=y
CONFIG_EAP_TLV=y
CONFIG_EAP_SAKE=y
CONFIG_EAP_GPSK=y
CONFIG_EAP_GPSK_SHA256=y
CONFIG_EAP_EKE=y
CONFIG_EAP_TNC=y
CFLAGS += -DTNC_CONFIG_FILE=\"tnc/tnc_config\"
LIBS += -rdynamic
CONFIG_EAP_FAST=y
CONFIG_EAP_IKEV2=y
CONFIG_IPV6=y
CONFIG_DRIVER_NONE=y
CONFIG_PKCS12=y

[dr.n (dr.n)]

- raspian buster