hw/arm: Add SPI to Allwinner A10

The Allwinner A10 SPI controller is added to the Allwinner A10
description, so it is available when Cubieboard is emulated.

Update the documentation for Cubieboard to indicate SPI availability.

Signed-off-by: Strahinja Jankovic <strahinja.p.jankovic@gmail.com>
Message-id: 20241001221349.8319-3-strahinja.p.jankovic@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
index f1e9816..0d658ea 100644
--- a/hw/arm/Kconfig
+++ b/hw/arm/Kconfig
@@ -328,6 +328,7 @@
     select ALLWINNER_WDT
     select ALLWINNER_EMAC
     select ALLWINNER_I2C
+    select ALLWINNER_A10_SPI
     select AXP2XX_PMU
     select SERIAL_MM
     select UNIMP