Use the same /etc/resolve.conf in kdump initrd if it's managed manually

.kexec-tools.metadata

@@ -0,0 +1,3 @@
+80ac3f5e77d3c79883edadf14428734db4720009 eppic-e8844d3.tar.gz
+ed15f191adee22ab0721ba62af1cae67eb981670 kexec-tools-2.0.27.tar.xz
+98cae2b1062871905795918c32b6d46ccd115074 makedumpfile-1.7.4.tar.gz

dracut-module-setup.sh

@@ -596,10 +596,10 @@ kdump_install_resolv_conf() {
     #
     # [1] https://bugzilla.gnome.org/show_bug.cgi?id=690404
     # [2] https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/configuring_and_managing_networking/manually-configuring-the-etc-resolv-conf-file_configuring-and-managing-networking
-    systemctl -q is-enabled systemd-resolved && return 0
+    systemctl -q is-enabled systemd-resolved 2> /dev/null && return 0
     inst "$_resolv_conf"
     if NetworkManager --print-config | grep -qs "^dns=none"; then
-        echo "[main]\ndns=none" > "$_nm_conf_dir"/90-dns-none.conf
+        printf "[main]\ndns=none\n" > "${initdir}/${_nm_conf_dir}"/90-dns-none.conf
     fi
 }