Make Sub kernel and operator stateless

- Rename NEArithmeticSubstractionKernel to CpuSubKernel and move files appropriately

- Add CpuSub under src/runtime/cpu/operators

Partially resolves: COMPMID-4007

Signed-off-by: Sheri Zhang <sheri.zhang@arm.com>
Change-Id: I4754ca9101d82dccacca744be6d069764a9c6b55
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/4868
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Pablo Marquez Tello <pablo.tello@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/Android.bp b/Android.bp
index 185097d..8d6182f 100644
--- a/Android.bp
+++ b/Android.bp
@@ -220,7 +220,6 @@
         "src/core/MultiImageInfo.cpp",
         "src/core/NEON/kernels/NEAbsoluteDifferenceKernel.cpp",
         "src/core/NEON/kernels/NEAccumulateKernel.cpp",
-        "src/core/NEON/kernels/NEArithmeticSubtractionKernel.cpp",
         "src/core/NEON/kernels/NEBatchNormalizationLayerKernel.cpp",
         "src/core/NEON/kernels/NEBatchToSpaceLayerKernel.cpp",
         "src/core/NEON/kernels/NEBitwiseAndKernel.cpp",
@@ -419,6 +418,7 @@
         "src/core/cpu/kernels/CpuFloorKernel.cpp",
         "src/core/cpu/kernels/CpuPermuteKernel.cpp",
         "src/core/cpu/kernels/CpuReshapeKernel.cpp",
+        "src/core/cpu/kernels/CpuSubKernel.cpp",
         "src/core/cpu/kernels/activation/NEON/fp16.cpp",
         "src/core/cpu/kernels/activation/NEON/fp32.cpp",
         "src/core/cpu/kernels/activation/NEON/qasymm8.cpp",
@@ -439,6 +439,10 @@
         "src/core/cpu/kernels/add/sve/qsymm16.cpp",
         "src/core/cpu/kernels/floor/NEON/fp16.cpp",
         "src/core/cpu/kernels/floor/NEON/fp32.cpp",
+        "src/core/cpu/kernels/sub/neon/integer.cpp",
+        "src/core/cpu/kernels/sub/neon/qasymm8.cpp",
+        "src/core/cpu/kernels/sub/neon/qasymm8_signed.cpp",
+        "src/core/cpu/kernels/sub/neon/qsymm16.cpp",
         "src/core/gpu/cl/kernels/ClBatchConcatenateKernel.cpp",
         "src/core/gpu/cl/kernels/ClDepthConcatenateKernel.cpp",
         "src/core/gpu/cl/kernels/ClHeightConcatenateKernel.cpp",
@@ -790,6 +794,7 @@
         "src/runtime/cpu/operators/CpuFloor.cpp",
         "src/runtime/cpu/operators/CpuPermute.cpp",
         "src/runtime/cpu/operators/CpuReshape.cpp",
+        "src/runtime/cpu/operators/CpuSub.cpp",
         "src/runtime/gpu/cl/operators/ClConcatenate.cpp",
         "utils/CommonGraphOptions.cpp",
         "utils/GraphUtils.cpp",