dev-libs/libltdl: Sync with Gentoo

It's from Gentoo commit a1a498b77d74a9904808cdf9a3943f995ebeae00.

sdk_container/src/third_party/portage-stable/dev-libs/libltdl/libltdl-2.4.7-r1.ebuild

@@ -0,0 +1,39 @@
+# Copyright 1999-2023 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI="7"
+
+# Please bump with sys-devel/libtool.
+
+inherit multilib-minimal flag-o-matic
+
+MY_P="libtool-${PV}"
+
+DESCRIPTION="A shared library tool for developers"
+HOMEPAGE="https://www.gnu.org/software/libtool/"
+SRC_URI="mirror://gnu/libtool/${MY_P}.tar.xz"
+S="${WORKDIR}"/${MY_P}/libltdl
+
+LICENSE="GPL-2"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~loong ~m68k ~mips ~ppc ~ppc64 ~riscv ~s390 ~sparc ~x86 ~x64-cygwin ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~sparc-solaris ~sparc64-solaris ~x64-solaris ~x86-solaris"
+IUSE="static-libs"
+# libltdl doesn't have a testsuite.
+
+BDEPEND="app-arch/xz-utils"
+
+multilib_src_configure() {
+	append-lfs-flags
+	ECONF_SOURCE="${S}" \
+	econf \
+		--enable-ltdl-install \
+		$(use_enable static-libs static)
+}
+
+multilib_src_install() {
+	emake DESTDIR="${D}" install
+
+	# While the libltdl.la file is not used directly, the m4 ltdl logic
+	# keys off of its existence when searching for ltdl support. # bug #293921
+	#use static-libs || find "${D}" -name libltdl.la -delete
+}