[Vulkan] Fix bug in GRU op (#78945)
Summary:
All of the current Vulkan API Tests of the GRU op, use the same H_in and H_out sizes (H_in = 384 and H_out = 384). Which means, these tests don't test the behavior when H_in != H_out.
There is indeed a bug: H_in is used at some point to split the weights/biases when it should have been H_out (the hidden_size).
Differential Revision: D36895889
Pull Request resolved: https://github.com/pytorch/pytorch/pull/78945
Approved by: https://github.com/SS-JIA
