boot_serial: espressif: enable erase progressively option on serial recovery

Signed-off-by: Almir Okato <almir.okato@espressif.com>
diff --git a/boot/espressif/port/esp_mcuboot.c b/boot/espressif/port/esp_mcuboot.c
index 3035515..088749c 100644
--- a/boot/espressif/port/esp_mcuboot.c
+++ b/boot/espressif/port/esp_mcuboot.c
@@ -364,6 +364,14 @@
     return 0;
 }
 
+int flash_area_sector_from_off(uint32_t off, struct flash_sector *sector)
+{
+    sector->fs_off = (off / FLASH_SECTOR_SIZE) * FLASH_SECTOR_SIZE;
+    sector->fs_size = FLASH_SECTOR_SIZE;
+
+    return 0;
+}
+
 int flash_area_id_from_multi_image_slot(int image_index, int slot)
 {
     BOOT_LOG_DBG("%s", __func__);