Fix the following error/warn seen with make dtbs_check

arm,smmu-venus@d40000: $nodename:0: 'arm,smmu-venus@d40000' does not match '^iommu@[0-9a-f]*'
arm,smmu-venus@d40000: clock-names:0: 'bus' was expected
arm,smmu-venus@d40000: clock-names:1: 'iface' was expected

by rename nodename to "iommu".
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Link: https://lore.kernel.org/r/20200106102305.27059-1-stanimir.varbanov@linaro.org
[bjorn: Added padding of address to 8 digits]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>