vbrun5, vbrun6: fix install check.  vc2005trial: fix regression caused by 7zip installing into its own wineprefix.
vbrun5, vbrun6: fix install check.  vc2005trial: fix regression caused by 7zip installing into its own wineprefix.

git-svn-id: b92d2e39cfa237656594b3bc53d4cd3ef2bf6eca@278 98bf863f-ac88-fb5c-4855-c94565d26d3c

Winetricks/winetricks,Winetricks/winetricks