Revert "Silence cling test error until after the break."

This reverts commit 16b0a0b8.

The error seems to be fixed but we forgot to update the test.

interpreter/cling/test/Autoloading/AutoForwarding.C

@@ -7,10 +7,6 @@
 //------------------------------------------------------------------------------
 
 // RUN: cat %s | %cling -I%S -Xclang -verify
-//
-//   XFAIL: *
-//   until enum autoloading is fixed.
-//
 // Test FwdPrinterTest
 
 // Test similar to ROOT-7037