net: moxa: Remove braces from single-line body

Remove unnecessary braces from single-line if statement
This warning is found using checkpatch.pl
Signed-off-by: NSZ Lin <sz.lin@moxa.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/moxa/moxart_ether.c

@@ -269,9 +269,8 @@ static int moxart_rx_poll(struct napi_struct *napi, int budget)
 		priv->rx_head = rx_head;
 	}
 
-	if (rx < budget) {
+	if (rx < budget)
 		napi_complete_done(napi, rx);
-	}
 
 	priv->reg_imr |= RPKT_FINISH_M;
 	writel(priv->reg_imr, priv->base + REG_INTERRUPT_MASK);