Update spirv_reflect.h

Co-authored-by: Spencer Fricke <[email protected]>

spirv_reflect.h

@@ -432,7 +432,7 @@ typedef struct SpvReflectInterfaceVariable {
   const char*                         semantic;
   SpvReflectDecorationFlags           decoration_flags;
 
-  // The builtin id if the variable is a builtin, and -1 otherwise.
+  // The builtin id (SpvBuiltIn) if the variable is a builtin, and -1 otherwise.
   int                                 built_in;
   SpvReflectNumericTraits             numeric;
   SpvReflectArrayTraits               array;