LinAlg Validation: Validate Matrix `K` Dimension

[V-FEXrt]

From the spec

The minimum and maximum K dimension for matrices is hardware dependent and varies by scope. The table below describes the maximums enforced by HLSL and DXIL validation.

Matrix Scope	Scalar element dimensions
Thread	[4,128]
Wave	[4,128]
ThreadGroup	[1, 1024]

[V-FEXrt]

Open questions: For accumulator matrices, which dimension is the K dim in terms of validation? Should both dims just be validated?

Ans: We don't validate either actually!