MAINTAINERS: update Amitkumar's email address

His email is bouncing, and he'd like to use this new one.

Cc: Amitkumar Karwar <amitkarwar@gmail.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Ganapathi Bhat <gbhat@marvell.com>
Cc: Xinming Hu <huxm@marvell.com>
Signed-off-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>

MAINTAINERS

@@ -7857,7 +7857,7 @@ S:	Maintained
 F:	drivers/net/ethernet/marvell/mvneta.*
 
 MARVELL MWIFIEX WIRELESS DRIVER
-M:	Amitkumar Karwar <akarwar@marvell.com>
+M:	Amitkumar Karwar <amitkarwar@gmail.com>
 M:	Nishant Sarmukadam <nishants@marvell.com>
 M:	Ganapathi Bhat <gbhat@marvell.com>
 M:	Xinming Hu <huxm@marvell.com>