fs: littlefs: remove dependency on flash map from FILE_SYSTEM_LITTLEFS

LittleFS may be used not only for Flash devices, we can use it for block
devices too. So, I have changed dependency rules and remove dependency
on flash map from FILE_SYSTEM_LITTLEFS.

Signed-off-by: Laczen JMS <laczenjms@gmail.com>
Signed-off-by: Mykola Kvach <mykola_kvach@epam.com>
diff --git a/subsys/fs/Kconfig.littlefs b/subsys/fs/Kconfig.littlefs
index e659a7b..50ebf75 100644
--- a/subsys/fs/Kconfig.littlefs
+++ b/subsys/fs/Kconfig.littlefs
@@ -6,8 +6,6 @@
 config FILE_SYSTEM_LITTLEFS
 	bool "LittleFS support"
 	depends on FILE_SYSTEM
-	depends on FLASH_MAP
-	depends on FLASH_PAGE_LAYOUT
 	depends on ZEPHYR_LITTLEFS_MODULE
 	help
 	  Enables LittleFS file system support.
@@ -105,6 +103,15 @@
 
 endif # FS_LITTLEFS_FC_HEAP_SIZE <= 0
 
+config FS_LITTLEFS_FMP_DEV
+	bool "Support for littlefs on flash devices"
+	depends on FLASH_MAP
+	depends on FLASH_PAGE_LAYOUT
+	default y
+	help
+	  Enable this option to provide support for littlefs on flash devices
+	  (using the flash_map API).
+
 config FS_LITTLEFS_BLK_DEV
 	bool "Support for littlefs on block devices"
 	help