The README-FIPS.md file was still the one used from 1.1.1. We update it
with 3.0 specific information.
Fixes#14237
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14575)