Add dev-qt from an older version of the gentoo repo

Qt5 has been removed, we restore it since we still use it.

dev-qt/qtscxml/qtscxml-5.15.16.ebuild

@@ -0,0 +1,20 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+inherit qt5-build
+
+DESCRIPTION="State Chart XML (SCXML) support library for the Qt5 framework"
+
+if [[ ${QT5_BUILD_TYPE} == release ]]; then
+	KEYWORDS="amd64 arm arm64 ~riscv x86"
+fi
+
+IUSE=""
+
+DEPEND="
+	=dev-qt/qtcore-${QT5_PV}*
+	=dev-qt/qtdeclarative-${QT5_PV}*
+"
+RDEPEND="${DEPEND}"