remove unnecessary unsafe

Author: aapoalas

drv/auxflash-server/src/main.rs

@@ -254,7 +254,7 @@ impl ServerImpl {
         let mut write_addr = spare_slot as usize * SLOT_SIZE;
         // SAFETY: this cannot overflow as data_size is less or equal to
         // SLOT_SIZE and active_slot is valid for reads up to SLOT_SIZE.
-        let read_end = unsafe { read_addr.unchecked_add(data_size) };
+        let read_end = read_addr + data_size;
         while read_addr < read_end {
             let amount = (read_end - read_addr).min(buf.len());