QOperatingSystemVersion: clean up after QOSVBase extraction

When 3446313c7a5cd6005089866a7b20c9f28e132a0a extracted most functions
from QOperatingSystemVersion to a new unexported
QOperatingSystemVersionBase, for BC reasons, it kept the existing QOSV
methods as (inline or out-of-line) forwarders to the new QOSVBase
ones.

But the only ones that are actually still required are currentType(),
type(), and isAnyOfType(), because their Base equivalents use a
different enum type (we should probably make the OS Type an enum in
namespace Qt instead; other patch).

The others can just be REMOVED_SINCE, and should be, to make new code
use the base class implementations, where inlining and constexpr
properly work (they don't, on Windows, in exported classes).

Re-use the existing REMOVED_SINCE(6,3) block in removed_api.cpp to
move these functions there.

Amends 3446313c7a5cd6005089866a7b20c9f28e132a0a.

Reverts a tiny part of 215677818470e48e9090d7ae4411e1fea62207b8 (will
conflict in backports).

Pick-to: 6.6 6.5
Change-Id: I1d7ba784634ccd7c9ba5f7ceddb15b7787468d31
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
(cherry picked from commit 1214edc0d94fd8b3c0d2660879d9175256c14bbc)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/corelib/compat/removed_api.cpp

@@ -139,6 +139,16 @@ QLocale::Language QLocale::codeToLanguage(QStringView languageCode) noexcept
 
 #include "qoperatingsystemversion.h"
 
+QOperatingSystemVersion QOperatingSystemVersion::current()
+{
+    return QOperatingSystemVersionBase::current();
+}
+
+QString QOperatingSystemVersion::name() const
+{
+    return QOperatingSystemVersionBase::name();
+}
+
 int QOperatingSystemVersion::compare(const QOperatingSystemVersion &v1,
                                      const QOperatingSystemVersion &v2)
 {

src/corelib/global/qoperatingsystemversion.cpp

@@ -111,15 +111,11 @@ QT_BEGIN_NAMESPACE
 */
 
 /*!
+    \fn QOperatingSystemVersion::current()
     Returns a QOperatingSystemVersion indicating the current OS and its version number.
 
     \sa currentType()
 */
-QOperatingSystemVersion QOperatingSystemVersion::current()
-{
-    return QOperatingSystemVersionBase::current();
-}
-
 QOperatingSystemVersionBase QOperatingSystemVersionBase::current()
 {
     static const QOperatingSystemVersionBase v = current_impl();
@@ -306,11 +302,6 @@ int QOperatingSystemVersionBase::compare(QOperatingSystemVersionBase v1,
 
     \sa type()
 */
-QString QOperatingSystemVersion::name() const
-{
-    return QOperatingSystemVersionBase::name();
-}
-
 QString QOperatingSystemVersionBase::name(QOperatingSystemVersionBase osversion)
 {
     switch (osversion.type()) {

src/corelib/global/qoperatingsystemversion.h

@@ -236,13 +236,16 @@ public:
     {
     }
 
+#if QT_CORE_REMOVED_SINCE(6, 3) || defined(Q_QDOC)
     static QOperatingSystemVersion current();
+#endif
 
     static constexpr OSType currentType()
     {
         return OSType(QOperatingSystemVersionBase::currentType());
     }
 
+#if QT_CORE_REMOVED_SINCE(6, 3) || defined(Q_QDOC)
     QVersionNumber version() const { return QOperatingSystemVersionBase::version(); }
 
     constexpr int majorVersion() const { return QOperatingSystemVersionBase::majorVersion(); }
@@ -251,10 +254,13 @@ public:
 
     constexpr int segmentCount() const
     { return QOperatingSystemVersionBase::segmentCount(); }
+#endif // QT_CORE_REMOVED_SINCE(6, 3)
 
     constexpr OSType type() const { return OSType(QOperatingSystemVersionBase::type()); }
     QT7_ONLY(Q_CORE_EXPORT) bool isAnyOfType(std::initializer_list<OSType> types) const;
-    QT7_ONLY(Q_CORE_EXPORT) QString name() const;
+#if QT_CORE_REMOVED_SINCE(6, 3) || defined(Q_QDOC)
+    QString name() const;
+#endif
 
 private:
     QOperatingSystemVersion() = default;