[SIL Builder] Fixup non-Asserts build again

Author: DougGregor

include/swift/SIL/SILBuilder.h

@@ -473,7 +473,10 @@ class SILBuilder {
     return createAllocBox(loc, SILBoxType::get(fieldType.getASTType()), Var,
                           hasDynamicLifetime, reflection,
                           usesMoveableValueDebugInfo,
-                          /*skipVarDeclAssert*/ false, hasPointerEscape);
+#ifndef NDEBUG
+                          /*skipVarDeclAssert*/ false,
+#endif
+                          hasPointerEscape);
   }
 
   AllocBoxInst *createAllocBox(SILLocation Loc, CanSILBoxType BoxType,