Modify uencrypt to support any cipher provided by ssl library.
Original tool supported only AES-128-CBC to decrypt the config
mtd of Arcadyan WG430223/WG443223.
TP-Link Deco S4 has mtd configuration encrypted with DES-ECB,
so make the cipher generic to support both routers.
Signed-off-by: Nick French <nickfrench@gmail.com>
Reviewed-by: Eneas U de Queiroz >cotequeiroz@gmail.com>