MAINTAINERS: Update tg3 maintainer

Signed-off-by: NSiva Reddy Kallam <siva.kallam@broadcom.com>
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Acked-by: NPrashant Sreedharan <prashant@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -2424,6 +2424,7 @@ F:	include/linux/bcm963xx_nvram.h
 F:	include/linux/bcm963xx_tag.h
 
 BROADCOM TG3 GIGABIT ETHERNET DRIVER
+M:	Siva Reddy Kallam <siva.kallam@broadcom.com>
 M:	Prashant Sreedharan <prashant@broadcom.com>
 M:	Michael Chan <mchan@broadcom.com>
 L:	netdev@vger.kernel.org