arm64: dts: qcom: sdm630-nile: correct duplicated reserved memory node

SoC DTSI already comes with 85800000 reserved memory node, so assume the
author wanted to update its length.  This fixes dtbs W=1 warning:

  Warning (unique_unit_address_if_enabled): /reserved-memory/qhee-code@85800000: duplicate unit-address (also used in node /reserved-memory/reserved@85800000)

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230419211921.79871-1-krzysztof.kozlowski@linaro.org