dwc-xlgmac: remove Jie Deng as co-maintainer

Jose Abreu is working on this driver and I will leave Synopsys soon.
Thus it does not seem appropriate for me to be a co-maintainer anymore.
Signed-off-by: NJie Deng <jiedeng@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -13289,7 +13289,6 @@ F:	include/linux/platform_data/dma-dw.h
 F:	drivers/dma/dw/
 
 SYNOPSYS DESIGNWARE ENTERPRISE ETHERNET DRIVER
-M:	Jie Deng <jiedeng@synopsys.com>
 M:	Jose Abreu <Jose.Abreu@synopsys.com>
 L:	netdev@vger.kernel.org
 S:	Supported