[perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstring fail on darwin

attached patch fixes this issue by trying to fix the wrong symlink in Configure
and fix or skip the broken locale in t/loc_tools.

• [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstring fail on darwin by Reini Urban via RT
• Re: [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstringfail on darwin by H.Merijn Brand
• Re: [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstring fail on darwin by H. Merijn Brand via RT
• Re: [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstring failon darwin by Jarkko Hietaniemi
• Re: [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstring fail on darwin by Jarkko Hietaniemi via RT
• Re: [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstringfail on darwin by Karl Williamson
• Re: [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstring fail on darwin by karl williamson via RT
• [perl #122296] POSIX::setlocale(0, "zh_CN.GB18030") mbstring fail on darwin by Reini Urban via RT