MAINTAINERS: Add a maintainer for Microsemi switches

Microsemi has been bought by Microchip and Microchip is supporting those
switches.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: NWoojung Huh <Woojung.Huh@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -9906,6 +9906,7 @@ F:	Documentation/scsi/smartpqi.txt
 
 MICROSEMI ETHERNET SWITCH DRIVER
 M:	Alexandre Belloni <alexandre.belloni@bootlin.com>
+M:	Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>
 L:	netdev@vger.kernel.org
 S:	Supported
 F:	drivers/net/ethernet/mscc/