New slimbus DT schema expect only SLIMbus bus nodes to be named
"slimbus".  In case of Qualcomm SLIMbus NGD, the bus node is what was
called "ngd".
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220928152027.489543-9-krzysztof.kozlowski@linaro.org