Changes to enable FP16 in armv8a multi_isa

* This is the initial patch to start working on enabling fp16 in all
  multi_isa builds. More changes are required in the way we register
  the kernels using the macro REGISTER_FP16_NEON.

* In this patch we add the capability to build the fp16 files in listed in
  filelist.json with the correct arch option to enable FP16

* This patch is required towards building an universal multi_isa binary
  where fp16 is enable.

* Enable REGISTER_FP16_NEON macro for all builds by removing
  __ARM_FEATURE_FP16_VECTOR_ARITHMETIC guard from the macro definition.
  The macro has to be used across all types of builds.

Change-Id: I99f4c273f6ee04cad3c097e5e374200f48568fa9
Signed-off-by: Pablo Marquez Tello <pablo.tello@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/10682
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Jakub Sujak <jakub.sujak@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Benchmark: Arm Jenkins <bsgcomp@arm.com>
diff --git a/docs/user_guide/release_version_and_change_log.dox b/docs/user_guide/release_version_and_change_log.dox
index 6d27ae3..13f4e9e 100644
--- a/docs/user_guide/release_version_and_change_log.dox
+++ b/docs/user_guide/release_version_and_change_log.dox
@@ -44,6 +44,8 @@
 v24.01 Public major release
  - Remove the legacy 'libarm_compute_core' library. This library is an artifact of Compute Library's legacy library architecture and no longer serves any purpose.
   You should link only to the main `libarm_compute` library for core functionality.
+ - New features
+   - Add support for FP16 in all multi_isa builds.
 
 v23.11 Public major release
  - New features