secur32: fix the schannel tests crashing on Vista.

[Reece Dunn]

The inbound test was passing NULL as the pointer to credentials, which
is causing Vista to crash.

Pass &cred instead, matching the outbound test.

- Reece
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: 0006-secur32-fix-the-schannel-tests-crashing-on-Vista.txt
Url: http://www.winehq.org/pipermail/wine-patches/attachments/20080730/29336910/attachment.txt