NormalizationLayer changes to enable fp16 in armv8a multi_isa builds

    * Moved the template arm_compute::normalize_float to impl.h because
      we need to instantiate it from both NENormalizationLayerKernel.cpp
      and src/cpu/kernels/norm_layer/generic/neon/fp16.cpp

    * Changes in filelist.json: added a new fp16.cpp file for the float16_t kernels

    * Replaced the guard __ARM_FEATURE_FP16_VECTOR_ARITHMETIC in
      NENormalizationLayerKernel by ARM_COMPUTE_ENABLE_FP16 so that
      the fp16 kernels can be compiled in for multi_isa builds

    * Moved fp32 kernels to the corresponding file
      src/cpu/kernels/norm_layer/generic/neon/fp32.cpp

    * Partially resolves MLCE-1102

Change-Id: I3f2eb2ed0b6c7f68092b17872b85082fbb5f39e2
Signed-off-by: Pablo Marquez Tello <pablo.tello@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/10739
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Viet-Hoa Do <viet-hoa.do@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Benchmark: Arm Jenkins <bsgcomp@arm.com>
diff --git a/src/BUILD.bazel b/src/BUILD.bazel
index a22632e..6ffc2eb 100644
--- a/src/BUILD.bazel
+++ b/src/BUILD.bazel
@@ -794,6 +794,8 @@
 	"cpu/kernels/meanstddevnorm/generic/neon/fp32.cpp",
 	"cpu/kernels/meanstddevnorm/generic/neon/impl.cpp",
 	"cpu/kernels/meanstddevnorm/generic/neon/qasymm8.cpp",
+	"cpu/kernels/norm_layer/generic/neon/fp16.cpp",
+	"cpu/kernels/norm_layer/generic/neon/fp32.cpp",
 	"cpu/kernels/pool2d/neon/fp16.cpp",
 	"cpu/kernels/pool2d/neon/fp32.cpp",
 	"cpu/kernels/pool2d/neon/nchw/all.cpp",