tst_toolsupport: make the i386 case really about i386

Specifically, don't use it for either of the x86-64 ABIs (LP64 and
ILP32). The generic case below should work for everyone.

Fixes: QTBUG-122720
Change-Id: I01ec3c774d9943adb903fffd17b75fc79095e089
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
(cherry picked from commit 24245d2a85cbcd503816027067aa72995e3ac2ac)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

tests/auto/other/toolsupport/tst_toolsupport.cpp

@@ -38,6 +38,7 @@ template <typename T, typename K>
 size_t pmm_to_offsetof(T K:: *pmm)
 {
 #ifdef Q_CC_MSVC
+
     // Even on 64 bit MSVC uses 4 byte offsets.
     quint32 ret;
 #else
@@ -114,10 +115,10 @@ void tst_toolsupport::offsets_data()
         QTestData &data = QTest::newRow("QFilePrivate::fileName")
                 << pmm_to_offsetof(&QFilePrivate::fileName);
         // Please heed the comment at the top of this file when changing one of these lines:
-#ifdef Q_PROCESSOR_X86
+#ifdef Q_PROCESSOR_X86_32
         // x86 32-bit has weird alignment rules. Refer to QtPrivate::AlignOf in
         // qglobal.h for more details.
-        data << 264 << 424;
+        data << 264 << -1;
 #else
         data << 300 << 424;
 #endif