configs/olimex_a20_olinuxino_lime: uboot 2021.10 needs openssl
Uboot 2021.10 needs openssl so enable it.
Fixes:
https://gitlab.com/buildroot.org/buildroot/-/jobs/1723730020
Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>