Silence MSVC warning about 64-bit conversion (loss of data)

One of the reasons why we use "int" everywhere: to avoid this annoyance
about different types and having to explicitly cast to silence the
compiler.

qsslsocket_openssl.cpp(690) : warning C4267: 'argument' : conversion from 'size_t' to 'int', possible loss of data

Change-Id: Ia0aac2f09e9245339951ffff13c8bdad334ce108
Reviewed-by: Richard J. Moore <rich@kde.org>

src/network/ssl/qsslsocket_openssl.cpp

@@ -687,7 +687,7 @@ void QSslSocketPrivate::resetDefaultEllipticCurves()
     if (q_EC_get_builtin_curves(builtinCurves.data(), curveCount) == curveCount) {
         for (size_t i = 0; i < curveCount; ++i) {
             QSslEllipticCurve curve;
-            curve.id = builtinCurves[i].nid;
+            curve.id = builtinCurves[int(i)].nid;
             curves.append(curve);
         }
     }