Created by: DannyIsFunny

Issue fusion_elementwise_activation kernels are not registered on x86 backends, causing that lite_elementwise_activation_fuse_pass can not operate on x86 backend. This pass is used for fusing elementwise kernel and its neighboring activationkernel to reduce time costing and data swapping. Effect of Curren PR Register fusion_elementwise_activation kernel to enable lite_elementwise_activation_fuse_pass on x86 backend.