[MPS] Handle compatible inputs to where (#85946)
Inputs with different number of dimensions but compatible shapes were being rejected
e.g. x.shape = [10,1,10]
y.shape = [10,10]
cond.shape = [10,10,1]
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85946
Approved by: https://github.com/malfet
