implement littlefs for stm32 (#5987)

Co-authored-by: GUVWAF <78759985+GUVWAF@users.noreply.github.com>
Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: Daniel Peter Chokola <dan.chokola@gmail.com>
Co-authored-by: Mark Trevor Birss <markbirss@gmail.com>
Co-authored-by: Austin <vidplace7@gmail.com>

src/platform/stm32wl/LittleFS.h

@@ -0,0 +1,41 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 hathach for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef INTERNALFILESYSTEM_H_
+#define INTERNALFILESYSTEM_H_
+
+#include "STM32_LittleFS.h"
+
+class LittleFS : public STM32_LittleFS
+{
+  public:
+    LittleFS(void);
+
+    // overwrite to also perform low level format (sector erase of whole flash region)
+    bool begin(void);
+};
+
+extern LittleFS InternalFS;
+
+#endif /* INTERNALFILESYSTEM_H_ */