USB: Removing NULL check for pool since dma_pool_destroy is safe

Removing NULL check for pool since dma_pool_destroy is safe
Signed-off-by: Salil Kapur <salilkapur93@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/buffer.c

@@ -101,12 +101,8 @@ void hcd_buffer_destroy(struct usb_hcd *hcd)
 		return;
 
 	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
-		struct dma_pool *pool = hcd->pool[i];
-
-		if (pool) {
-			dma_pool_destroy(pool);
-			hcd->pool[i] = NULL;
-		}
+		dma_pool_destroy(hcd->pool[i]);
+		hcd->pool[i] = NULL;
 	}
 }