arm64: dts: fsd: minor whitespace cleanup around '='

The DTS code coding style expects exactly one space before and after '='
sign.
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Link: https://lore.kernel.org/r/20230702185012.43699-2-krzysztof.kozlowski@linaro.orgSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>