Get rid of 1024-byte limit for displaying variables as well.

This basically makes all of unparse_path() and its derivatives into
snprintf()-like functions, so we don't have to have static buffers.

Signed-off-by: Peter Jones <pjones@redhat.com>
Handle some other device paths.

Add support for Vendor-Defined Messaging Device Paths as well as
FVFILE() and FVVOL()

Signed-off-by: Peter Jones <pjones@redhat.com>