If device is unbound, the soc_dev should be unregistered to prevent
memory leak.

Fixes: a2974c9c ("soc: add driver for the ARM RealView")
Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/20240825-soc-dev-fixes-v1-3-ff4b35abed83@linaro.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>