version/tests: Write-strings warning fix

[Andrew Talbot]

Changelog:
    version/tests: Write-strings warning fix.

diff -urN a/dlls/version/tests/info.c b/dlls/version/tests/info.c
--- a/dlls/version/tests/info.c	2006-12-15 17:26:02.000000000 +0000
+++ b/dlls/version/tests/info.c	2006-12-16 12:00:54.000000000 +0000
@@ -233,7 +233,7 @@
     {
     /* this test crashes on WinNT4
      */
-    boolret = VerQueryValueA( pVersionInfo, "\\", (LPVOID *)&pFixedVersionInfo, 0);
+    boolret = VerQueryValueA( pVersionInfo, backslash, (LPVOID *)&pFixedVersionInfo, 0);
     ok (boolret, "VerQueryValue failed: GetLastError = 0x%08x\n", GetLastError());
     }