fetch2/wget: fixup case with no useful netrc data

fetch2/wget: fixup case with no useful netrc data

Commit 873e33d0479e977520106b65d149ff1799195bf6 [fetch2/wget:
add Basic Auth from netrc to checkstatus()] causes "Fetcher failure
for URL: 'https://www.example.com/'. URL https://www.example.com/
doesn't work." on new builds when a user has a .netrc file but there
is no default and no matching host. The call to netrc.authenticators()
will return None in these cases and the attempted assignment to the
3-tuple will raise a TypeError exception. Add the TypeError to the
exceptions caught to get around this issue.

Signed-off-by: Mark Asselstine <mark.asselstine@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>