soc: nordic: add vpr_launcher in sysbuild

`SB_CONFIG_VPR_LAUNCHER` can now be used in building a VPR target,
to enable automatic building of image that will launch the VPR.

Signed-off-by: Marcin Szymczyk <marcin.szymczyk@nordicsemi.no>

Author: masz-nordic

soc/nordic/Kconfig.sysbuild

@@ -0,0 +1,4 @@
+# Copyright (c) 2024 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+rsource "common/vpr/Kconfig.sysbuild"

soc/nordic/common/vpr/Kconfig.sysbuild

@@ -0,0 +1,11 @@
+# Copyright (c) 2024 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+config VPR_LAUNCHER
+	bool "VPR launcher"
+	default y
+	depends on (SOC_NRF54H20_CPUPPR || SOC_NRF54L15_ENGA_CPUFLPR)
+	help
+	  Include VPR launcher in build.
+	  VPR launcher is a minimal sample built for an ARM core that starts given VPR core.
+	  It is based on samples/basic/minimal with an appropriate snippet.

soc/nordic/sysbuild.cmake

@@ -0,0 +1,31 @@
+# Copyright (c) 2024 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+if(SB_CONFIG_VPR_LAUNCHER)
+  set(launcher_core "cpuapp")
+  string(REPLACE "/" ";" launcher_quals ${BOARD_QUALIFIERS})
+  list(LENGTH launcher_quals launcher_quals_len)
+  list(GET launcher_quals 1 launcher_soc)
+  list(GET launcher_quals 2 launcher_vpr)
+
+  string(REPLACE "cpu" "" launcher_vpr ${launcher_vpr})
+
+  if(launcher_quals_len EQUAL 4)
+    list(GET launcher_quals 3 launcher_variant)
+    set(launcher_vpr ${launcher_vpr}-${launcher_variant})
+  endif()
+
+  string(CONCAT launcher_board ${BOARD} "/" ${launcher_soc} "/" ${launcher_core})
+
+  set(image "vpr_launcher")
+
+  ExternalZephyrProject_Add(
+    APPLICATION ${image}
+    SOURCE_DIR ${ZEPHYR_BASE}/samples/basic/minimal
+    BOARD ${launcher_board}
+  )
+
+  string(CONCAT launcher_snippet "nordic-" ${launcher_vpr})
+
+  sysbuild_cache_set(VAR ${image}_SNIPPET APPEND REMOVE_DUPLICATES ${launcher_snippet})
+endif()