MAINTAINERS: add NXP linux team maillist as i.MX reviewer

Add NXP linux team upstream maillist as reviewer

Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

MAINTAINERS

@@ -1403,6 +1403,7 @@ ARM/FREESCALE IMX / MXC ARM ARCHITECTURE
 M:	Shawn Guo <shawnguo@kernel.org>
 M:	Sascha Hauer <kernel@pengutronix.de>
 R:	Fabio Estevam <fabio.estevam@nxp.com>
+R:	NXP Linux Team <linux-imx@nxp.com>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux.git