[LyX/master] Follow-up for change a66ee4109e - guard Qt 5.4 code with version check

[Stephan Witt]

commit deae5ea23a507b9560278382f89c4219d38b7245
Author: Stephan Witt <switt at lyx.org>
Date:   Thu Dec 8 18:05:28 2022 +0100

    Follow-up for change a66ee4109e - guard Qt 5.4 code with version check
---
 src/frontends/qt/GuiAbout.cpp |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/src/frontends/qt/GuiAbout.cpp b/src/frontends/qt/GuiAbout.cpp
index 16f8be4..35375c9 100644
--- a/src/frontends/qt/GuiAbout.cpp
+++ b/src/frontends/qt/GuiAbout.cpp
@@ -294,12 +294,14 @@ static QString version(bool const plain = false)
 		out << '\n';
 	else
 		out << "</p><p>";
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 4, 0))
 	out << toqstr(bformat(_("OS Version (run-time): %1$s"),
 		qstring_to_ucs4(QSysInfo::prettyProductName())));
 	if (plain)
 		out << '\n';
 	else
 		out << "</p><p>";
+#endif
 	out << toqstr(bformat(_("Python detected: %1$s"), from_utf8(os::python())));
 	if (!plain)
 		out << toqstr("</p></body></html>");