docs/system/arm: Add placeholder doc for exynos4 boards

Add a placeholder doc for the exynos4 boards nuri and smdkc210.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Message-id: 20241018141332.942844-5-peter.maydell@linaro.org

MAINTAINERS

@@ -716,6 +716,7 @@ L: qemu-arm@nongnu.org
 S: Odd Fixes
 F: hw/*/exynos*
 F: include/hw/*/exynos*
+F: docs/system/arm/exynos.rst
 
 Calxeda Highbank
 M: Rob Herring <robh@kernel.org>

docs/system/arm/exynos.rst

@@ -0,0 +1,9 @@
+Exynos4 boards (``nuri``, ``smdkc210``)
+=======================================
+
+These are machines which use the Samsung Exynos4210 SoC, which has Cortex-A9 CPUs.
+
+``nuri`` models the Samsung NURI board.
+
+``smdkc210`` models the Samsung SMDKC210 board.
+

docs/system/target-arm.rst

@@ -90,6 +90,7 @@ undocumented; you can get a complete list by running
    arm/digic
    arm/cubieboard
    arm/emcraft-sf2
+   arm/exynos
    arm/fby35
    arm/musicpal
    arm/kzm