sys-libs/liburing: add 'examples' and 'test' use flags

By default liburing will build tests and examples but these fail to
build on musl systems so we sed them out if not needed.

Closes: https://bugs.gentoo.org/888956
Closes: https://github.com/gentoo/gentoo/pull/29563
Signed-off-by: Steffen Winter <steffen.winter@proton.me>
Signed-off-by: Florian Schmaus <flow@gentoo.org>

sys-libs/liburing/liburing-2.3-r2.ebuild

@@ -17,9 +17,9 @@ fi
 LICENSE="MIT"
 SLOT="0/2" # liburing.so major version
 
-IUSE="static-libs"
+IUSE="examples static-libs test"
 # fsync test hangs forever
-RESTRICT="test"
+RESTRICT="test !test? ( test )"
 
 # At least installed headers need <linux/*>, bug #802516
 DEPEND=">=sys-kernel/linux-headers-5.1"
@@ -39,6 +39,13 @@ src_prepare() {
 		sed -i "/^Version:/s@[[:digit:]\.]\+@${PV}@" ${PN}.spec || die
 	fi
 
+	if ! use examples; then
+		sed -e '/examples/d' Makefile -i || die
+	fi
+	if ! use test; then
+		sed -e '/test/d' Makefile -i || die
+	fi
+
 	multilib_copy_sources
 }