This applies when the shape_cast is simply for dropping unit dims, and
the result rank is >= 2.
This simplifies the transpose making it possible for other ArmSME
legalization patterns to handle it.
Example:
```mlir
%0 = vector.transpose %vector, [3, 0, 1, 2]
: vector<1x1x4x[4]xf32> to vector<[4]x1x1x4xf32>
%1 = vector.shape_cast %0 : vector<[4]x1x1x4xf32> to vector<[4]x4xf32>
```
```mlir
%0 = vector.shape_cast %arg0 : vector<1x1x4x[4]xf32> to vector<4x[4]xf32>
%1 = vector.transpose %0, [1, 0] : vector<4x[4]xf32> to vector<[4]x4xf32>
```
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