[PATCH libctf] Fix a number of build problems found on Solaris and NetBSD

[Jose E. Marchesi]

    > This needs approval from someone with global write privs for the
    > binutils/objdump.c part.
    
    OK, but you're fine without global approval.  Changing the library API
    is up to your discretion as the library maintainer, and that obviously
    requires updates elsewhere.

I just pushed the patch in behalf of Nick.
Thanks.