iio: adc: rcar: Fix up Marek Vasut MAINTAINERS entry

Use up to date address. No functional change.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Author: Marek Vasut

MAINTAINERS

@@ -22602,7 +22602,7 @@ F:	Documentation/devicetree/bindings/mtd/renesas-nandc.yaml
 F:	drivers/mtd/nand/raw/renesas-nand-controller.c
 
 RENESAS R-CAR GYROADC DRIVER
-M:	Marek Vasut <marek.vasut@gmail.com>
+M:	Marek Vasut <marek.vasut+renesas@mailbox.org>
 L:	linux-iio@vger.kernel.org
 S:	Supported
 F:	Documentation/devicetree/bindings/iio/adc/renesas,rcar-gyroadc.yaml