initiator: Fix overflow in percentage calculation

When drive size was larger than 8 GB, LED indicator and logged percentage
would reset to 0 midway through the transfer.

Author: PetteriAimonen

src/BlueSCSI_initiator.cpp

@@ -116,7 +116,7 @@ static void scsiInitiatorUpdateLed()
     // Update status indicator, the led blinks every 5 seconds and is on the longer the more data has been transferred
     const int period = 256;
     int phase = (millis() % period);
-    int duty = g_initiator_state.sectors_done * period / g_initiator_state.sectorcount;
+    int duty = (int64_t)g_initiator_state.sectors_done * period / g_initiator_state.sectorcount;
 
     // Minimum and maximum time to verify that the blink is visible
     if (duty < 50) duty = 50;