Merge various CTF fixes from illumos
2942 CTF tools need to handle files which legitimately lack data
2978 ctfconvert still needs to ignore legitimately dataless files on SPARC
Illumos Revisions: 13745:6b3106b4250f
13754:7231b684c18b
Reference:
https://www.illumos.org/issues/2942
https://www.illumos.org/issues/2978
MFC after: 3 weeks