sample/fs: Add nrf54l15pdk/nrf54l15/cpuapp to fs_sample

Adds custom overlay and config allowing the sample to run on
the nrf54l15pdk.

Signed-off-by: Dominik Ermel <dominik.ermel@nordicsemi.no>

samples/subsys/fs/fs_sample/boards/nrf54l15pdk_nrf54l15_cpuapp.conf

@@ -0,0 +1,12 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+CONFIG_DISK_DRIVERS=y
+CONFIG_DISK_DRIVER_FLASH=y
+# There may be no files on internal SoC flash, so this Kconfig
+# options has ben enabled to create some if listing does not
+# find in the first place.
+CONFIG_FS_SAMPLE_CREATE_SOME_ENTRIES=y

samples/subsys/fs/fs_sample/boards/nrf54l15pdk_nrf54l15_cpuapp.overlay

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/* Because FAT FS needs at least 64kiB partition and default
+ * storage_partition is 36kiB for this board, we need to reorganize
+ * partitions to get at least 64KiB.
+ */
+/delete-node/ &slot0_partition;
+/delete-node/ &slot1_partition;
+/delete-node/ &slot0_ns_partition;
+/delete-node/ &slot1_ns_partition;
+/delete-node/ &storage_partition;
+
+&cpuapp_rram {
+	partitions {
+		compatible = "fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		slot0_partition: parition@10000 {
+			reg = <0x00010000 DT_SIZE_K(300)>;
+		};
+		slot1_partition: partition@5b000 {
+			reg = <0x0005b000 DT_SIZE_K(300)>;
+		};
+
+		storage_partition: partition@a6000 {
+			label = "storage";
+			reg = <0x000a6000 DT_SIZE_K(128)>;
+		};
+	};
+};
+
+/ {
+	msc_disk0 {
+		status="okay";
+		compatible = "zephyr,flash-disk";
+		partition = <&storage_partition>;
+		disk-name = "SD";
+		cache-size = <512>;
+	};
+};

samples/subsys/fs/fs_sample/sample.yaml

@@ -43,6 +43,9 @@ tests:
     extra_args:
       - OVERLAY_CONFIG=boards/nrf52840dk_nrf52840_ram_disk.conf
       - DTC_OVERLAY_FILE=boards/nrf52840dk_nrf52840_ram_disk_region.overlay
+  sample.filesystem.fat_fs.nrf54l15pdk:
+    build_only: true
+    platform_allow: nrf54l15pdk/nrf54l15/cpuapp
   sample.filesystem.fat_fs.nrf52840dk_nrf52840.qspi:
     build_only: true
     platform_allow: nrf52840dk/nrf52840