Log Message:
www/curl: Accomodate SSLCERTBUNDLE

Rather than letting openssl perform default validation, curl passes in
an explicit request to...  use the certificates in the default
location.  In cases where SSLCERTBUNDLE is defined (because the system
uses a bundle instead of the traditonal directory of trust anchors),
pass that to curl's configure.

As proposed on tech-pkg by Thomas Orgis, without objections.