dns: normalize record type read interactively in dnsrecord_add
    
    When dnsrecord_add is called without options in interactive mode, it
    prompts the user to enter a record type. The record type is expected to be
    upper case further in the code, which causes non-upper case values not to
    work correctly.
    
    Fix this issue by upper casing the value after it is read.
    
    https://fedorahosted.org/freeipa/ticket/6203
    
    Reviewed-By: Martin Basti <mbasti@redhat.com>