STYLE: Remove unused SSE2 compiler flag checks in CMake configuration

Visual Studio 2022 warns of ignored flags.

In Visual Studio 2012 and later versions, SSE2 is enabled by default.
https://learn.microsoft.com/en-us/cpp/build/reference/arch-x86?view=msvc-170

Originally prompted by 1000's of warnings:
cl : Command line warning D9025 : overriding '/arch:SSE' with '/arch:SSE2'

For all modern Linux packaging workflows (wheels, C++ libs, distros):
	x86_64: do NOT specify -msse2 — wasteful and redundant.
	Portability is retained, the x86-64 baseline includes SSE2

Author: hjmjohnson

CMake/ITKSetStandardCompilerFlags.cmake

@@ -446,7 +446,11 @@ macro(check_compiler_platform_flags)
       )
     endif()
 
-    check_sse2_flags(ITK_SSE2_CFLAGS_IF_AVAILABLE)
+    if(CMAKE_SIZEOF_VOID_P EQUAL 4)
+      # Setting sse2 flags only make sense on 32 bit architectures
+      # on 64bit systems, sse2 support is required, and compiler support is defaulted
+      check_sse2_flags(ITK_SSE2_CFLAGS_IF_AVAILABLE)
+    endif()
     set(
       ITK_REQUIRED_CXX_FLAGS
       "${ITK_REQUIRED_CXX_FLAGS} ${ITK_SSE2_CFLAGS_IF_AVAILABLE}"