QtMiscUtils: add missing toAsciiUpper(), use it in moc

... to make moc code locale-independent.

The C toupper function is locale-dependent. Given the right locale
(Türkiye, e.g.), toupper('i') is either

- İ (LATIN CAPITAL LETTER I WITH DOT ABOVE; if representable) or
- i (unchanged; if it isn't)

Both results are wrong for the present use-case.

Fix by adding QtMiscTools::toAsciiUpper(), complementing existing
toAsciiLower(), and using that. It's private API, but moc.h, despite
the name, is not a public header.

Pick-to: 6.5 6.4 6.2 5.15
Task-number: QTBUG-109235
Change-Id: Iaf071ba2113b672aa0aed3da6a4e1d47fb659365
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qtools_p.h

@@ -54,6 +54,11 @@ constexpr inline char toAsciiLower(char ch) noexcept
     return (ch >= 'A' && ch <= 'Z') ? ch - 'A' + 'a' : ch;
 }
 
+constexpr inline char toAsciiUpper(char ch) noexcept
+{
+    return (ch >= 'a' && ch <= 'z') ? ch - 'a' + 'A' : ch;
+}
+
 constexpr inline int caseCompareAscii(char lhs, char rhs) noexcept
 {
     const char lhsLower = QtMiscUtils::toAsciiLower(lhs);

src/tools/moc/moc.h

@@ -13,7 +13,8 @@
 #include <qjsonobject.h>
 #include <qversionnumber.h>
 #include <stdio.h>
-#include <ctype.h>
+
+#include <private/qtools_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -102,7 +103,7 @@ struct PropertyDef
 {
     bool stdCppSet() const {
         QByteArray s("set");
-        s += toupper(name[0]);
+        s += QtMiscUtils::toAsciiUpper(name[0]);
         s += name.mid(1);
         return (s == write);
     }