tcl/board: Add nRF54L15-DK config file

This patch adds support for the nRF54L15 development kit from Nordic
Semiconductor.

Change-Id: I5e362227fed3982ef21f36e41aade196e0ac7031
Signed-off-by: Marc Schink <dev@zapb.de>
Reviewed-on: https://review.openocd.org/c/openocd/+/8610
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: jenkins

tcl/board/nordic/nrf54l15-dk.cfg

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+#
+# Nordic Semiconductor nRF54L15 Development kit
+# https://www.nordicsemi.com/Products/Development-hardware/nRF54L15-DK
+#
+
+source [find interface/jlink.cfg]
+source [find target/nordic/nrf54l.cfg]