package/containerd: support crun as runtime

crun is a drop-in replacement for runc. If crun is enabled, but runc is
not, we already install an impersonation symlink, so we do not need to
force runc if crun is enabled. Still, runc is the default if crun is not
enabled.

Signed-off-by: TIAN Yuanhao <tianyuanhao3@163.com>
Reviewed-by: Christian Stewart <christian@paral.in>
[yann.morin.1998@free.fr: split into its own patch]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/containerd/Config.in

@@ -5,7 +5,7 @@ config BR2_PACKAGE_CONTAINERD
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_TOOLCHAIN_USES_UCLIBC # runc
 	depends on BR2_USE_MMU # util-linux
-	select BR2_PACKAGE_RUNC # runtime dependency
+	select BR2_PACKAGE_RUNC if !BR2_PACKAGE_CRUN # runtime dependency
 	select BR2_PACKAGE_UTIL_LINUX # runtime dependency
 	select BR2_PACKAGE_UTIL_LINUX_BINARIES
 	select BR2_PACKAGE_UTIL_LINUX_PIVOT_ROOT