Move the HAVE_SYSCTLBYNAME definition out of X86, remove the previous workaround

CMakeLists.txt

@@ -272,10 +272,6 @@ if(MACOSX AND NOT IOS)
 	endif()
 endif()
 
-if(IOS)
-	add_definitions(-DHAVE_SYSCTLBYNAME)
-endif()
-
 include(FindThreads)
 
 if(APPLE)

ext/cmake/cpu_features/CMakeLists.txt

@@ -154,10 +154,8 @@ endif()
 target_include_directories(cpu_features
   PUBLIC $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/cpu_features>
 )
-if(PROCESSOR_IS_X86)
-  if(APPLE)
-    target_compile_definitions(cpu_features PRIVATE HAVE_SYSCTLBYNAME)
-  endif()
+if(APPLE)
+  target_compile_definitions(cpu_features PRIVATE HAVE_SYSCTLBYNAME)
 endif()
 add_library(CpuFeature::cpu_features ALIAS cpu_features)