lsbcc libtool fixup incomplete

[Jeff Johnson]

While looking for something else, noticed the lsbcc "libtool fixup" isn't
particularly useful on certain architectures. Here's a snippet to illustrate:

    /*
     * We do a first level filter on /usr/lib
     * If the file is in /usr/lib and has '.so' in it someplace,
     * we assume that it is a shared lib.
     * This takes care of ld scripts like /usr/lib/libc.so
     */

    /* check if the file is a shared lib */
    efile = OpenElfFile(optarg);
    if (!efile && strncmp(optarg, "/usr/lib", strlen("/usr/lib")) != 0) {
        return 0;
    }

Since for the 64-bit architectures the applicable files are in /usr/lib64, this
is going to miss stuff. Also, although some distros have unified /lib (or
lib64) and /usr/lib (or lib64), some have not, so a sensible check should still
look in both directories.

Admittedly the libtool fixup is not very formal (it is designed to look at a
command line that may have been modified by libtool to put in full paths to
shared libraries instead of "-lfile" references), it could make a better effort
than it's doing.