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/qtx11extras/qtx11extras-5.15.16.ebuild

@@ -0,0 +1,22 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+inherit qt5-build
+
+DESCRIPTION="Linux/X11-specific support library for the Qt5 framework"
+
+if [[ ${QT5_BUILD_TYPE} == release ]]; then
+	KEYWORDS="amd64 arm arm64 ~hppa ~loong ppc ppc64 ~riscv x86"
+fi
+
+IUSE=""
+
+RDEPEND="
+	=dev-qt/qtcore-${QT5_PV}*
+	=dev-qt/qtgui-${QT5_PV}*[X]
+"
+DEPEND="${RDEPEND}
+	test? ( =dev-qt/qtwidgets-${QT5_PV}* )
+"