[MERGE #6041 @wyrichte] Fixing ARM64 build issues

Merge pull request #6041 from wyrichte:build/wyrichte/ARM64_cleanup

Author: wyrichte

lib/Backend/Func.cpp

@@ -1324,7 +1324,7 @@ Func::EndPhase(Js::Phase tag, bool dump)
     {
         Assert(!this->isPostLower);
         this->isPostLower = true;
-#ifndef _M_ARM    // Need to verify ARM is clean.
+#if !defined(_M_ARM) && !defined(_M_ARM64) // Need to verify ARM is clean.
         DbCheckPostLower dbCheck(this);
         dbCheck.CheckNestedHelperCalls();
 #endif

lib/Runtime/Base/ThreadContextInfo.cpp

@@ -507,7 +507,7 @@ ThreadContextInfo::SetValidCallTargetInternal(
 #endif
             )
         {
-            _guard_check_icall((uintptr_t)callTargetAddress);
+            _GUARD_CHECK_ICALL((uintptr_t)callTargetAddress);
         }
 
         if (PHASE_TRACE1(Js::CFGPhase))

lib/Runtime/Base/ThreadContextInfo.h

@@ -179,3 +179,6 @@ uintptr_t ShiftAddr(const ThreadContextInfo*const context, T* address)
 
 uintptr_t ShiftAddr(const ThreadContextInfo*const context, uintptr_t address);
 
+#ifndef _GUARD_CHECK_ICALL
+#define _GUARD_CHECK_ICALL _guard_check_icall
+#endif