[Fix] remove useless header not needed in kernel header (#60927)

Author: qili93

paddle/phi/kernels/apply_per_channel_scale_kernel.h

@@ -16,10 +16,6 @@
 
 #include "paddle/phi/core/dense_tensor.h"
 
-#include "paddle/phi/backends/gpu/gpu_context.h"
-#include "paddle/phi/common/datatype_traits.h"
-#include "paddle/phi/core/kernel_registry.h"
-
 namespace phi {
 
 template <typename T, typename Context>