[fr] Make histogram example more realistic

[Moelf]

Right now, the histogram example https://github.com/JuliaGPU/KernelAbstractions.jl/blob/110d78475861281298ec930c7292af903e8360d0/examples/histogram.jl assumes the data value range is small, something like 0-128 or 0-1024 etc. In reality, we would probably have a pre-defined binning and so on

I will give it a try