[pocket fft] turning on pocketfft flag (#81670)

Summary:
enabling AT_POCKETFFT_ENABLED@ flag and adding the appropriate dependencies to aten-cpu

moved mkl files from
`aten_cpu_source_non_codegen_list` to
`aten_native_source_non_codegen_list`

Test Plan:
After building testing binaries for both android and ios targets

### iOS
`fbcode/aibench/specifications/frameworks/pytorch/ios/build.sh`

Submitted benchmarks with the new binaries supporting pocketfft here:
https://www.internalfb.com/intern/aibench/details/245253003946591

### Android
`fbcode/aibench/specifications/frameworks/pytorch/android/arm64/build.sh`

Submitted Benchmarks with the new binaries supporting pocket fft here:
https://www.internalfb.com/intern/aibench/details/406253690682941

### Build Size Impact

Success: igios-pika on D37790257-V7

☷[pocket fft] turning on pocketfft flag☷
Diff: https://fburl.com/diff/exkploof
Unigraph Explorer: https://fburl.com/mbex/aipdzaqo

Changes for variation [arm64 + 3x assets]:
```Compressed  : -473 B (-0.00%) => 86.69 MiB
Uncompressed: +2.4 KiB (+0.00%) => 187.71 MiB
```

Reviewed By: kimishpatel

Differential Revision: D37790257

Pull Request resolved: https://github.com/pytorch/pytorch/pull/81670
Approved by: https://github.com/kit1980

buckbuild.bzl

@@ -134,6 +134,7 @@ THIRD_PARTY_LIBS = {
     "kineto": ["//xplat/kineto/libkineto:libkineto", "//third_party:libkineto"],
     "libkineto_headers": ["//xplat/kineto/libkineto:libkineto_headers", "//third_party:libkineto_headers"],
     "omp": ["//xplat/third-party/linker_lib:omp", "//third_party:no-op"],
+    "pocketfft": ["//third-party/pocket_fft:pocketfft", "//third_party:pocketfft_header"],
     "psimd": ["//xplat/third-party/psimd:psimd", "//third_party:psimd"],
     "pthreadpool": ["//xplat/third-party/pthreadpool:pthreadpool", "//third_party:pthreadpool"],
     "pthreadpool_header": ["//xplat/third-party/pthreadpool:pthreadpool_header", "//third_party:pthreadpool_header"],
@@ -1022,7 +1023,7 @@ def define_buck_targets(
             "0",
             "--replace",
             "@AT_POCKETFFT_ENABLED@",
-            "0",
+            "1",
             "--replace",
             "@AT_NNPACK_ENABLED@",
             "ATEN_NNPACK_ENABLED_FBXPLAT",
@@ -1880,6 +1881,7 @@ def define_buck_targets(
                 third_party("cpuinfo"),
                 third_party("glog"),
                 third_party("XNNPACK"),
+                third_party("pocketfft"),
             ],
             compiler_flags = get_aten_compiler_flags(),
             exported_preprocessor_flags = get_aten_preprocessor_flags(),

build_variables.bzl

@@ -1062,10 +1062,6 @@ aten_cpu_source_non_codegen_list = [
     "aten/src/ATen/native/AutogradComposite.cpp",
     "aten/src/ATen/native/DispatchStub.cpp",
     "aten/src/ATen/native/UpSample.cpp",
-    "aten/src/ATen/native/mkl/LinearAlgebra.cpp",
-    "aten/src/ATen/native/mkl/SparseBlasImpl.cpp",
-    "aten/src/ATen/native/mkl/SparseCsrLinearAlgebra.cpp",
-    "aten/src/ATen/native/mkl/SpectralOps.cpp",
     "aten/src/ATen/native/mkldnn/BinaryOps.cpp",
     "aten/src/ATen/native/mkldnn/Conv.cpp",
     "aten/src/ATen/native/mkldnn/Copy.cpp",
@@ -1361,6 +1357,10 @@ aten_native_source_non_codegen_list = [
     "aten/src/ATen/native/WeightNorm.cpp",
     "aten/src/ATen/native/group_norm.cpp",
     "aten/src/ATen/native/layer_norm.cpp",
+    "aten/src/ATen/native/mkl/LinearAlgebra.cpp",
+    "aten/src/ATen/native/mkl/SparseBlasImpl.cpp",
+    "aten/src/ATen/native/mkl/SparseCsrLinearAlgebra.cpp",
+    "aten/src/ATen/native/mkl/SpectralOps.cpp",
     "aten/src/ATen/native/nested/NestedTensorMath.cpp",
     "aten/src/ATen/native/nested/NestedTensorTransformerFunctions.cpp",
     "aten/src/ATen/native/sparse/ParamUtils.cpp",

third_party/BUCK.oss

@@ -75,6 +75,16 @@ cxx_library(
     visibility = ["PUBLIC"],
 )
 
+cxx_library(
+    name = "pocketfft_header",
+    header_namespace = "",
+    exported_headers = {
+        "pocketfft_hdronly.h": "pocketfft/pocketfft_hdronly.h",
+    },
+    reexport_all_header_dependencies = True,
+    visibility = ["PUBLIC"],
+)
+
 cxx_library(
     name = "FXdiv",
     header_namespace = "",