Is the `*` implementation necessary?

[matbesancon]

There is a redirection in LinearAlgebra implementing * as mul between two matrices.

This means all these methods:
https://github.com/JuliaLinearAlgebra/ArrayLayouts.jl/blob/master/src/ArrayLayouts.jl#L225

could potentially be removed. They can cause a number of ambiguities downstream, especially for a widely used package like ArrayLayouts