Remove note about .CHM on network drives.

Should be more or less moot since 67d3791de8.

windows/README-msi.txt

@@ -24,12 +24,6 @@ Alternatively, you can always run pscp.exe by its full pathname, e.g.
 (Note that a Command Prompt that was already open before you ran the
 installer will not have inherited the update of PATH.)
 
-Some versions of Windows will refuse to run HTML Help files (.CHM)
-if they are installed on a network drive. If you have installed
-PuTTY on a network drive, you might want to check that the help file
-works properly. If not, see http://support.microsoft.com/kb/896054
-for information on how to solve this problem.
-
 What do I do if it doesn't work?
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