usbboot: Delay on each bulk transfer chunk

Change-type: patch
Signed-off-by: Juan Cruz Viotti <juan@balena.io>

lib/sdk/adapters/usbboot/protocol.js

@@ -249,7 +249,7 @@ exports.write = (device, endpoint, buffer) => {
         return Bluebird.fromCallback((callback) => {
           console.log(`SENDING CHUNK: ${chunk.length}`)
           endpoint.transfer(chunk, callback)
-        })
+        }).delay(USB_REQUEST_DELAY_MS)
       })
     })
 }