QSPIFormat: add option to perform a full erase

Author: pennam

libraries/STM32H747_System/examples/QSPIFormat/QSPIFormat.ino

@@ -78,7 +78,14 @@ void setup() {
       return;
     }
 
-    root->erase(0x0, root->get_erase_size());
+    Serial.println("Do you want to perform a full erase of the QSPI flash before proceeding? Y/[n]");
+    if (true == waitResponse()) {
+      root->erase(0x0, root->size());
+    } else {
+      // Erase only the first sector containing the MBR
+      root->erase(0x0, root->get_erase_size());
+    }
+
     MBRBlockDevice::partition(root, 1, 0x0B, 0, 1 * 1024 * 1024);
     MBRBlockDevice::partition(root, 2, 0x0B, 1 * 1024 * 1024,  6 * 1024 * 1024);
     MBRBlockDevice::partition(root, 3, 0x0B, 6 * 1024 * 1024,  7 * 1024 * 1024);