MemAccessUtils: handle the obsolete allocVector builtin

This builtin was removed. But to be able to parse old Swift.swiftinterface files it is required to handle the builtin in MemAccessUtils.

Author: eeckstein

lib/SIL/Utils/MemAccessUtils.cpp

@@ -2616,6 +2616,7 @@ static void visitBuiltinAddress(BuiltinInst *builtin,
     case BuiltinValueKind::DeallocRaw:
     case BuiltinValueKind::StackAlloc:
     case BuiltinValueKind::UnprotectedStackAlloc:
+    case BuiltinValueKind::AllocVector:
     case BuiltinValueKind::StackDealloc:
     case BuiltinValueKind::Fence:
     case BuiltinValueKind::StaticReport: