MAINTAINERS: update Peter Chen's email address

Using kernel.org as my email address.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index afe3a5c..c16a2e8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3881,7 +3881,7 @@
 F:	drivers/mtd/nand/raw/cadence-nand-controller.c
 
 CADENCE USB3 DRD IP DRIVER
-M:	Peter Chen <peter.chen@nxp.com>
+M:	Peter Chen <peter.chen@kernel.org>
 M:	Pawel Laszczak <pawell@cadence.com>
 R:	Roger Quadros <rogerq@kernel.org>
 R:	Aswath Govindraju <a-govindraju@ti.com>
@@ -4163,7 +4163,7 @@
 F:	Documentation/translations/zh_CN/
 
 CHIPIDEA USB HIGH SPEED DUAL ROLE CONTROLLER
-M:	Peter Chen <Peter.Chen@nxp.com>
+M:	Peter Chen <peter.chen@kernel.org>
 L:	linux-usb@vger.kernel.org
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/peter.chen/usb.git
@@ -18404,7 +18404,7 @@
 F:	drivers/usb/host/ohci*
 
 USB OTG FSM (Finite State Machine)
-M:	Peter Chen <Peter.Chen@nxp.com>
+M:	Peter Chen <peter.chen@kernel.org>
 L:	linux-usb@vger.kernel.org
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/peter.chen/usb.git