ndctl v47

ndctl: release v47

This release reflects the ABI of the first kernel with libnvdimm
support, v4.2.

New apis:
    ndctl_bus_cmd_new_ars_cap
    ndctl_bus_cmd_new_ars_start
    ndctl_bus_cmd_new_ars_status
    ndctl_cmd_ars_cap_get_size
    ndctl_cmd_ars_in_progress
    ndctl_cmd_ars_num_records
    ndctl_cmd_ars_get_record_addr
    ndctl_cmd_ars_get_record_len
    ndctl_namespace_disable_invalidate

Fixes:
    ndctl_btt_enable now triggers a re-scan for new btt seeds