samples: subsys: fs_little fs on stm32u585 disco in xip

Gives a sample to execute the little fs on external memory map
(XiP) where the lfs1 partition is in internal mcu flash
The application is built/linked/stored in the external NOR
flash on slot1 partition.

Signed-off-by: Francois Ramu <[email protected]>

Author: FRASTM

samples/subsys/fs/littlefs/boards/b_u585i_iot02a.conf

@@ -5,3 +5,5 @@
 #
 
 CONFIG_FS_LITTLEFS_FC_HEAP_SIZE=8192
+
+CONFIG_STM32_MEMMAP=y

samples/subsys/fs/littlefs/boards/b_u585i_iot02a.overlay

@@ -5,6 +5,10 @@
  */
 
  / {
+	chosen {
+		zephyr,code-partition = &slot1_partition;
+	};
+
 	fstab {
 		compatible = "zephyr,fstab";
 		lfs1: lfs1 {
@@ -21,13 +25,10 @@
 	};
 };
 
-&mx25lm51245 {
+&flash0 {
 	partitions {
-		/delete-node/ partition;
-
-		/* Use the whole flash for the filesystem. */
-		lfs1_partition: partition@0 {
-			reg = <0x00000000 DT_SIZE_M(64)>;
+		lfs1_partition: partition@d0000 {
+			reg = <0x000d0000 DT_SIZE_K(64)>;
 		};
 	};
 };