erasing MBR table before creating a new partitioning scheme

Author: andreagilardoni

Diff for: libraries/STM32H747_System/examples/QSPIFormat/QSPIFormat.ino

@@ -60,6 +60,13 @@ void setup() {
   Serial.println("Do you want to proceed? Y/[n]");
 
   if (true == waitResponse()) {
+    if (root.init() != QSPIF_BD_ERROR_OK) {
+      Serial.println(F("Error: QSPI init failure."));
+      return;
+    }
+
+    root.erase(0x0, root.get_erase_size());
+
     mbed::MBRBlockDevice::partition(&root, 1, 0x0B, 0, 1024 * 1024);
     if(default_scheme) {
       mbed::MBRBlockDevice::partition(&root, 3, 0x0B, 14 * 1024 * 1024, 14 * 1024 * 1024);