hw/arm/npcm7xx: remove setting of mp-affinity

hw/arm/npcm7xx: remove setting of mp-affinity

The value of the mp-affinity property being set in npcm7xx_realize is
always the same as the default value it would have when arm_cpu_realizefn
is called if the property is not set here. So there is no need to set
the property value in npcm7xx_realize function.

Signed-off-by: Dorjoy Chowdhury <dorjoychy111@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240504141733.14813-1-dorjoychy111@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>