MAINTAINERS: add myself as maintainer for xilinx axiethernet driver

I am maintaining xilinx axiethernet driver in xilinx tree and would like
to maintain it in the mainline kernel as well. Hence adding myself as a
maintainer. Also Anirudha and John has moved to new roles, so based on
request removing them from the maintainer list.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -17699,8 +17699,7 @@ F:	include/uapi/linux/dqblk_xfs.h
 F:	include/uapi/linux/fsmap.h
 
 XILINX AXI ETHERNET DRIVER
-M:	Anirudha Sarangi <anirudh@xilinx.com>
-M:	John Linn <John.Linn@xilinx.com>
+M:	Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
 S:	Maintained
 F:	drivers/net/ethernet/xilinx/xilinx_axienet*