MAINTAINERS: add gxp fan controller and documents

Add the gxp-fan-ctrl.c and gxp-fan-ctrl.rst in hwmon
driver/documentation.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
Reviewed-by: Guenter Roek <linux@roek-us.net>
Link: https://lore.kernel.org/r/20230103203654.59322-6-nick.hawkins@hpe.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>

MAINTAINERS

@@ -2280,13 +2280,16 @@ ARM/HPE GXP ARCHITECTURE
 M:	Jean-Marie Verdun <verdun@hpe.com>
 M:	Nick Hawkins <nick.hawkins@hpe.com>
 S:	Maintained
+F:	Documentation/hwmon/gxp-fan-ctrl.rst
 F:	Documentation/devicetree/bindings/arm/hpe,gxp.yaml
+F:	Documentation/devicetree/bindings/hwmon/hpe,gxp-fan-ctrl.yaml
 F:	Documentation/devicetree/bindings/spi/hpe,gxp-spifi.yaml
 F:	Documentation/devicetree/bindings/timer/hpe,gxp-timer.yaml
 F:	arch/arm/boot/dts/hpe-bmc*
 F:	arch/arm/boot/dts/hpe-gxp*
 F:	arch/arm/mach-hpe/
 F:	drivers/clocksource/timer-gxp.c
+F:	drivers/hwmon/gxp-fan-ctrl.c
 F:	drivers/spi/spi-gxp.c
 F:	drivers/watchdog/gxp-wdt.c