librdmacm: Support RAI_NUMERICHOST and no delay options

librdmacm: Support RAI_NUMERICHOST and no delay options

Add support similar to getaddrinfo AI_NUMERICHOST.  This
indicates that lengthy address resolution protocols should
not be used.  Also allow a caller of rdma_getaddrinfo to
indicate that lengthy route resolution protocols should not
be used.

Since rdma_getaddrinfo is a synchronous call, this allows a
user to obtain locally available data only without long
delays that may block an application thread.  Callers can then
use the asynchronous librdmacm calls to complete any missing
information.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>