openssl: allow ALL ciphers when allow-insecure-crypto is enabled

openssl: allow ALL ciphers when allow-insecure-crypto is enabled

Previously, the cipher list was set to "DEFAULT:+3DES:+RC4". However,
according to ciphers(1), the DEFAULT keyword cannot be combined with
other strings using the + characters. In other words, ":+3DES:+RC4" gets
ignored.

The user is opting into insecure behavior, so let's keep it simple and
just allow everything.

This change fixes the obsolete-server-crypto test when openconnect is
built against openssl-1.1.x.

Signed-off-by: Mike Gilbert <floppym@gentoo.org>