WFE2: Wire missed config elements to WFE object. (#3604)

This commit addresses two config elements that were defined but not
wired through to the WFE implementation object. Prior to this commit the
`c.WFE.DirectoryCAAIdentity` and `c.WFE.DirectoryWebsite` configuration
values were read and unmarshaled from config but not passed to the WFE.
After this commit these two config options will be picked up by the WFE
impl.

cmd/boulder-wfe2/main.go

@@ -219,6 +219,8 @@ func main() {
 	wfe.AllowOrigins = c.WFE.AllowOrigins
 	wfe.AcceptRevocationReason = c.WFE.AcceptRevocationReason
 	wfe.AllowAuthzDeactivation = c.WFE.AllowAuthzDeactivation
+	wfe.DirectoryCAAIdentity = c.WFE.DirectoryCAAIdentity
+	wfe.DirectoryWebsite = c.WFE.DirectoryWebsite
 
 	wfe.IssuerCert, err = cmd.LoadCert(c.Common.IssuerCert)
 	cmd.FailOnError(err, fmt.Sprintf("Couldn't read issuer cert [%s]", c.Common.IssuerCert))