!301 txgbe : fix arm32 compiler error warning in txgbe_main.c

Merge Pull Request from: @duanqiangwen 
 
This PR is to fix arm32 compiler error warning in txgbe_main.c

Kernel Issue:https://gitee.com/open_euler/dashboard?issue_id=I5Y6RT

warnning:
- build warning:
- drivers/net/ethernet/netswift/txgbe/txgbe_main.c: In function ‘txgbe_configure_isb’:


```
drivers/net/ethernet/netswift/txgbe/txgbe_main.c:3708:49: warning: right shift count >= width of type [-Wshift-count-overflow]

  wr32(hw, TXGBE_PX_ISB_ADDR_H, adapter->isb_dma >> 32);
                                                 ^~

drivers/net/ethernet/netswift/ngbe/ngbe_main.c: In function ‘ngbe_configure_isb’:
drivers/net/ethernet/netswift/ngbe/ngbe_main.c:3166:48: warning: right shift count >= width of type [-Wshift-count-overflow]
  wr32(hw, NGBE_PX_ISB_ADDR_H, adapter->isb_dma >> 32);
                                                ^~
```
 
 
Link:https://gitee.com/openeuler/kernel/pulls/301 
Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com> 
Reviewed-by: Zheng Zengkai <zhengzengkai@huawei.com> 
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> 

drivers/net/ethernet/netswift/txgbe/txgbe_main.c

@@ -3705,7 +3705,11 @@ void txgbe_configure_isb(struct txgbe_adapter *adapter)
 
 	wr32(hw, TXGBE_PX_ISB_ADDR_L,
 			adapter->isb_dma & DMA_BIT_MASK(32));
+#ifdef CONFIG_64BIT
 	wr32(hw, TXGBE_PX_ISB_ADDR_H, adapter->isb_dma >> 32);
+#else
+	wr32(hw, TXGBE_PX_ISB_ADDR_H, 0);
+#endif
 }
 
 void txgbe_configure_port(struct txgbe_adapter *adapter)