MINOR: cfgcond: add "awslc_api_atleast" and "awslc_api_before"

MINOR: cfgcond: add "awslc_api_atleast" and "awslc_api_before"

AWS-LC features are not easily tested with just the openssl version
constant. AWS-LC uses its own API versioning stored in the
AWSLC_API_VERSION constant.

This patch add the two awslc_api_atleast and awslc_api_before predicates
that help to check the AWS-LC API.