winhelp: Write-strings warning fix

[Andrew Talbot]

Changelog:
    winhelp: Write-strings warning fix.

diff -urN a/programs/winhelp/winhelp.c b/programs/winhelp/winhelp.c
--- a/programs/winhelp/winhelp.c	2006-05-23 13:49:31.000000000 +0100
+++ b/programs/winhelp/winhelp.c	2006-07-26 20:27:43.000000000 +0100
@@ -164,11 +164,12 @@
     MSG                 msg;
     LONG                lHash = 0;
     HLPFILE*            hlpfile;
-    char*               wndname = "main";
+    static CHAR         default_wndname[] = "main";
+    LPSTR               wndname = default_wndname;
     WINHELP_DLL*        dll;
 
     Globals.hInstance = hInstance;
-    
+
     /* Get options */
     while (*cmdline && (*cmdline == ' ' || *cmdline == '-'))
     {