Enable MSVC support for AArch64 code paths and Windows build fixes

[Harishmcw]

Summary

This PR improves MSVC compatibility for Windows on Arm64 by extending AArch64-specific code paths to also recognize _M_ARM64, and fixes the SCons build system to work correctly on native ARM64 Windows hosts.

Motivation

• While building OpenVINO for Windows on Arm64 using MSVC, several compilation failures and runtime crashes were encountered in ARM Compute Library due to ARM64-specific code being guarded only by aarch64.
• MSVC defines _M_ARM64 instead of aarch64, causing those code paths to be excluded.
  This resulted in compilation errors such as:

error C2039: 'NEReorderLayer': is not a member of 'arm_compute'
error C3646: unknown override specifier
error C4430: missing type specifier

• Additionally, the SCons build fails on native ARM64 Windows hosts because the assembler command template defaults to POSIX-style flags (-o) instead of MSVC-style (/Fo) that clang-cl expects.

Fix

This PR updates ARM64-specific code paths to support both GCC/Clang and MSVC by replacing architecture guards of the form:

#ifdef __aarch64__

with

#if defined(__aarch64__) || defined(_M_ARM64)

The changes include:

• ActivationLayerInfo.h — Enables ARM64-specific members and introduces an MSVC-compatible float16_t alias.
• LUTManager.h — Enables ARM64 lookup table definitions for MSVC.
• QuantizationInfo.h — Applies the ARM64 rounding policy for MSVC builds.
• NEReorderLayer.h — Makes NEReorderLayer available for _M_ARM64.

SConstruct

• Explicitly sets ASCOM and ASPPCOM for the Windows build. The os == 'windows' block already overrides AS to clang-cl, but doesn't set the command template.
• On native ARM64 Windows hosts, SCons fails to auto-detect MSVC and falls back to POSIX-style flags (-o), which clang-cl rejects. This fix completes the existing Windows overrides.