Adjust MSVC disabled optimization pragmas to be _MSC_VER only

Alter the #ifdef values from llvm#110986 and llvm#115292 to use _MSC_VER instead of _WIN32 to stop the pragmas being used on gcc/mingw builds

Noticed by @mstorsjo

Author: RKSimon

clang/lib/AST/ByteCode/Interp.cpp

@@ -1616,7 +1616,7 @@ bool Interpret(InterpState &S, APValue &Result) {
   }
 }
 // https://github.com/llvm/llvm-project/issues/102513
-#if defined(_WIN32) && !defined(__clang__) && !defined(NDEBUG)
+#if defined(_MSC_VER) && !defined(__clang__) && !defined(NDEBUG)
 #pragma optimize("", on)
 #endif
 

llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp

@@ -32,7 +32,7 @@ using namespace llvm;
 #define PASS_NAME "AArch64 Instruction Selection"
 
 // https://github.com/llvm/llvm-project/issues/114425
-#if defined(_WIN32) && !defined(__clang__) && !defined(NDEBUG)
+#if defined(_MSC_VER) && !defined(__clang__) && !defined(NDEBUG)
 #pragma inline_depth(0)
 #endif