bitbake: fetch2/wget: avoid 'maximum recursion depth' RuntimeErrors when handling...

bitbake: fetch2/wget: avoid 'maximum recursion depth' RuntimeErrors when handling 403 codes

The code says that some servers respond with 403 codes when they really
mean 405 codes. But we still need to account for legitimate 403 codes.

Before this change, I noticed that sstate mirror checking was taking a
very long time when I purposely entered incorrect credentials into my
.netrc file for our sstate mirror. Instrumenting the code, I discovered
tracebacks like the following for every mirror access attempt:

    File "/home/laplante/yocto/sources/poky/meta/classes/sstate.bbclass", line 839, in checkstatus
      fetcher.checkstatus()
    File "/home/laplante/yocto/sources/poky/bitbake/lib/bb/fetch2/__init__.py", line 1736, in checkstatus
      ret = try_mirrors(self, self.d, ud, mirrors, True)
    File "/home/laplante/yocto/sources/poky/bitbake/lib/bb/fetch2/__init__.py", line 1077, in try_mirrors
      ret = try_mirror_url(fetch, origud, uds[index], ld, check)
    File "/home/laplante/yocto/sources/poky/bitbake/lib/bb/fetch2/__init__.py", line 979, in try_mirror_url
      found = ud.method.checkstatus(fetch, ud, ld)
    File "/home/laplante/yocto/sources/poky/bitbake/lib/bb/fetch2/wget.py", line 337, in checkstatus
      opener.open(r)
    File "/usr/lib/python3.5/urllib/request.py", line 472, in open
      response = meth(req, response)
    File "/usr/lib/python3.5/urllib/request.py", line 582, in http_response
      'http', request, response, code, msg, hdrs)
    File "/usr/lib/python3.5/urllib/request.py", line 504, in error
      result = self._call_chain(*args)
    File "/usr/lib/python3.5/urllib/request.py", line 444, in _call_chain
      result = func(*args)
    File "/home/laplante/yocto/sources/poky/bitbake/lib/bb/fetch2/wget.py", line 280, in http_error_405
      unverifiable=True))
    File "/usr/lib/python3.5/urllib/request.py", line 472, in open
      response = meth(req, response)
    File "/usr/lib/python3.5/urllib/request.py", line 582, in http_response
      'http', request, response, code, msg, hdrs)
    File "/usr/lib/python3.5/urllib/request.py", line 504, in error
      result = self._call_chain(*args)
    File "/usr/lib/python3.5/urllib/request.py", line 444, in _call_chain
      result = func(*args)
    File "/home/laplante/yocto/sources/poky/bitbake/lib/bb/fetch2/wget.py", line 280, in http_error_405
      unverifiable=True))
    ...  (repeats until recursion depth is reached)

Solution is to make sure we only attempt the GET request once when handling 403/405 error codes.

(Bitbake rev: 18d4a31fdcec1f0e5d2199d6142f0ce833fca1a7)

Signed-off-by: Chris Laplante <chris.laplante@agilent.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>