main/linux-postmarketos-allwinner: enable TCPMSS match functionality
TCPMSS target (CONFIG_IP_NF_TARGET_TCPMSS) is already enabled but match (CONFIG_IP_NF_MATCH_TCPMSS) was not.
the rule
iptables -t nat -A POSTROUTING -o $GSMIF -m policy --dir out --pol ipsec -p tcp -m tcp --tcp-flags SYN,RST SYN -m tcpmss --mss 1199:9000 -j TCPMSS --set-mss 1200
is failing with the following error
iptables v1.8.7 (legacy): Couldn't load match `tcpmss':No such file or directory
Try `iptables -h' or 'iptables --help' for more information.