Simplify using distributive property of matrix multiplication

[CharlieL7]

• During the migraphx graph optimizations introduction presentation I showed a situation where we could have used the distributive property of matrix multiplication to produce a more optimized graph then what we currently do with horizontal fusions
• The property is that given that A, B, and C are matrices: AB + AC = A(B + C)
• In this situation I showed B and C were literal matrices, so rearranging the graph to do B + C first would reduce the number of GEMMs and literals.