shlwapi/tests: Use wine_dbgstr_guid() to trace REFIIDs.

dlls/shlwapi/tests/ordinal.c

@@ -1004,7 +1004,8 @@ static HRESULT WINAPI Disp_Invoke(
         EXCEPINFO *pExcepInfo,
         UINT *puArgErr)
 {
-    trace("%p %x %p %x %x %p %p %p %p\n",This,dispIdMember,riid,lcid,wFlags,pDispParams,pVarResult,pExcepInfo,puArgErr);
+    trace("%p %x %s %x %x %p %p %p %p\n", This, dispIdMember, wine_dbgstr_guid(riid), lcid, wFlags,
+          pDispParams, pVarResult, pExcepInfo, puArgErr);
 
     ok(dispIdMember == 0xa0 || dispIdMember == 0xa1, "Unknown dispIdMember\n");
     ok(pDispParams != NULL, "Invoked with NULL pDispParams\n");

dlls/shlwapi/tests/thread.c

@@ -52,7 +52,7 @@ static HRESULT WINAPI threadref_QueryInterface(IUnknown *iface, REFIID riid, LPV
 {
     threadref * This = impl_from_IUnknown(iface);
 
-    trace("unexpected QueryInterface(%p, %p, %p) called\n", This, riid, ppvObj);
+    trace("unexpected QueryInterface(%p, %s, %p) called\n", This, wine_dbgstr_guid(riid), ppvObj);
     *ppvObj = NULL;
     return E_NOINTERFACE;
 }