Add Diffie-Hellman group definitions for MODP groups in RFC 5114

Add Diffie-Hellman group definitions for MODP groups in RFC 5114

The groups 22, 23, and 24 are not based on a safe prime and generate a
prime order subgroup. As such, struct dh_group is also extended to
include the order for previously defined groups (q=(p-1)/2 since these
were based on a safe prime).

Signed-hostap: Jouni Malinen <j@w1.fi>