boards: sipeed: longan_nano: Add J-Link runner support

Adds the J-Link runner support for the longan_nano board.

Signed-off-by: Michael Arnold <marnold@baumer.com>
diff --git a/boards/sipeed/longan_nano/board.cmake b/boards/sipeed/longan_nano/board.cmake
index f58ea43..7cfcf34 100644
--- a/boards/sipeed/longan_nano/board.cmake
+++ b/boards/sipeed/longan_nano/board.cmake
@@ -7,6 +7,8 @@
 board_runner_args(openocd "--cmd-load=gd32vf103-load")
 board_runner_args(openocd "--cmd-post-verify=gd32vf103-post-verify")
 board_runner_args(dfu-util "--pid=28e9:0189" "--alt=0" "--dfuse")
+board_runner_args(jlink "--device=GD32VF103CBT6" "--speed=4000" "--iface=jtag" "--tool-opt=-jtagconf -1,-1 -autoconnect 1" "--reset-after-load")
 
 include(${ZEPHYR_BASE}/boards/common/openocd.board.cmake)
 include(${ZEPHYR_BASE}/boards/common/dfu-util.board.cmake)
+include(${ZEPHYR_BASE}/boards/common/jlink.board.cmake)