MAINTAINERS: Add hw/input/ads7846.c to the PXA2XX section

The code from hw/input/ads7846.c is only used by hw/arm/spitz.c,
so add this file to the same section where hw/arm/spitz.c is
listed.

Message-ID: <20231020060936.524988-3-thuth@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>

MAINTAINERS

@@ -928,6 +928,7 @@ F: hw/*/pxa2xx*
 F: hw/display/tc6393xb.c
 F: hw/gpio/max7310.c
 F: hw/gpio/zaurus.c
+F: hw/input/ads7846.c
 F: hw/misc/mst_fpga.c
 F: hw/adc/max111x.c
 F: include/hw/adc/max111x.h