MAINTAINERS: at91: Collect all pinctrl/gpio drivers in same entry

Andrei's address is not valid anymore, collect all pinctrl/gpio
entries in the common "PIN CONTROLLER - MICROCHIP AT91" one
and remove the PIOBU specific one.
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20190823083158.2649-1-nicolas.ferre@microchip.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

MAINTAINERS

@@ -10615,12 +10615,6 @@ M:	Nicolas Ferre <nicolas.ferre@microchip.com>
 S:	Supported
 F:	drivers/power/reset/at91-sama5d2_shdwc.c
 
-MICROCHIP SAMA5D2-COMPATIBLE PIOBU GPIO
-M:	Andrei Stefanescu <andrei.stefanescu@microchip.com>
-L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
-L:	linux-gpio@vger.kernel.org
-F:	drivers/gpio/gpio-sama5d2-piobu.c
-
 MICROCHIP SPI DRIVER
 M:	Nicolas Ferre <nicolas.ferre@microchip.com>
 S:	Supported
@@ -12679,6 +12673,7 @@ L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 L:	linux-gpio@vger.kernel.org
 S:	Supported
 F:	drivers/pinctrl/pinctrl-at91*
+F:	drivers/gpio/gpio-sama5d2-piobu.c
 
 PIN CONTROLLER - FREESCALE
 M:	Dong Aisheng <aisheng.dong@nxp.com>