DirectConv and Im2Col changes to enable fp16 in armv8a multi_isa builds

* FP16 kernels must be instantiated in fp16.cpp.
* Partially resolves MLCE-1102

Change-Id: Iab9c29dbfd89358f2f663862ff5010c88aeccf8c
Signed-off-by: Pablo Marquez Tello <pablo.tello@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/10496
Reviewed-by: Anitha Raj <Anitha.Raj@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Benchmark: Arm Jenkins <bsgcomp@arm.com>
diff --git a/filelist.json b/filelist.json
index d0a81f0..5bca241 100644
--- a/filelist.json
+++ b/filelist.json
@@ -1150,10 +1150,16 @@
               "src/core/NEON/kernels/convolution/winograd/weight_transforms/cpp_fp32_1x4_1x5.cpp",
               "src/core/NEON/kernels/convolution/winograd/weight_transforms/cpp_fp32_1x6_1x3.cpp",
               "src/cpu/kernels/directconv2d/nhwc/neon/impl.cpp",
+              "src/cpu/kernels/directconv2d/nhwc/neon/qasymm8.cpp",
               "src/cpu/kernels/directconv2d/nchw/all.cpp"
+
             ],
             "fp32": [
               "src/cpu/kernels/directconv2d/nhwc/neon/fp32.cpp"
+            ],
+            "fp16": [
+              "src/cpu/kernels/directconv2d/nchw/fp16.cpp",
+              "src/cpu/kernels/directconv2d/nhwc/neon/fp16.cpp"
             ]
           },
           "sve": {