staging/rdma/hfi1: Make firmware failure messages warnings

Make firmware validation failure and missing firmware messages
a warning since alternates can be tried.  Add an error message
when all attempts fail.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>