setupapi/tests: Write-strings warnings fix (1 of 2)

[Andrew Talbot]

Changelog:
    setupapi/tests: Write-strings warnings fix.

diff -urN a/dlls/setupapi/tests/devinst.c b/dlls/setupapi/tests/devinst.c
--- a/dlls/setupapi/tests/devinst.c	2006-07-21 21:10:02.000000000 +0100
+++ b/dlls/setupapi/tests/devinst.c	2006-08-05 16:29:12.000000000 +0100
@@ -36,11 +36,12 @@
     HDEVINFO devlist;
     BOOL ret;
     DWORD error;
+    static CHAR notnull[] = "NotNull";
     static const WCHAR machine[] = { 'd','u','m','m','y',0 };
 
     SetLastError(0xdeadbeef);
     /* create empty DeviceInfoList, but set Reserved to a value, which is not NULL */
-    devlist = SetupDiCreateDeviceInfoListExW(NULL, NULL, NULL, "NotNull");
+    devlist = SetupDiCreateDeviceInfoListExW(NULL, NULL, NULL, notnull);
 
     error = GetLastError();
     ok(devlist == INVALID_HANDLE_VALUE, "SetupDiCreateDeviceInfoListExW failed : %p %ld (expected %p)\n", devlist, error, INVALID_HANDLE_VALUE);