HAL_ChibiOS: enable HAL storage erase

libraries/AP_HAL_ChibiOS/Storage.cpp

@@ -380,4 +380,26 @@ bool Storage::healthy(void)
             (AP_HAL::millis() - _last_empty_ms < 2000u));
 }
 
+/*
+  erase all storage
+ */
+bool Storage::erase(void)
+{
+#if HAL_WITH_RAMTRON
+    if (_initialisedType == StorageBackend::FRAM) {
+        return AP_HAL::Storage::erase();
+    }
+#endif
+#ifdef USE_POSIX
+    if (_initialisedType == StorageBackend::SDCard) {
+        return AP_HAL::Storage::erase();
+    }
+#endif
+#ifdef STORAGE_FLASH_PAGE
+    return _flash.erase();
+#else
+    return false;
+#endif
+}
+
 #endif // HAL_USE_EMPTY_STORAGE

libraries/AP_HAL_ChibiOS/Storage.h

@@ -40,6 +40,7 @@ static_assert(CH_STORAGE_SIZE % CH_STORAGE_LINE_SIZE == 0,
 class ChibiOS::Storage : public AP_HAL::Storage {
 public:
     void init() override {}
+    bool erase() override;
     void read_block(void *dst, uint16_t src, size_t n) override;
     void write_block(uint16_t dst, const void* src, size_t n) override;