add glue for krb5_einval

lib/krb5/krb5_locl.h

@@ -188,6 +188,12 @@ struct _krb5_krb_auth_data;
 #define ALLOC(X, N) (X) = calloc((N), sizeof(*(X)))
 #define ALLOC_SEQ(X, N) do { (X)->len = (N); ALLOC((X)->val, (N)); } while(0)
 
+#ifndef __func__
+#define __func__ "unknown-function"
+#endif
+
+#define krb5_einval(context, argnum) _krb5_einval((context), __func__, (argnum))
+
 #ifndef PATH_SEP
 #define PATH_SEP ":"
 #endif