skip those. This handles the Protective MBR (PMBR) which consists
of a single partition of type 0xEE that covers the whole disk and
as such protects the GPT partitioning. We allow other partitions to
be present besides partitions of type 0xEE and as such interpret
partition type 0xEE as a "hands-off" partition only.
While here, fix g_mbrext_dumpconf to test if indent is NULL and
dump the data in a form that libdisk can grok. Change the logic
in g_mbr_dumpconf to match that of g_mbrext_dumpconf. This does
not change the output, but prevents a NULL-pointer dereference
when indent == NULL && pp == NULL.