Allow IP addresses to be specified in a URI.

Allow IP addresses to be specified in a URI.

Our checking here was a bit too aggressive, and did not permit an
IP address in a URI. IP's in a URI are allowed for things like CRLdp's
AIA, SAN URI's etc.). The check for this was also slightly flawed as
we would permit an IP if memory allocation failed while checking for
an IP.

Correct both issues.

ok tb@