8364296: Set IntelJccErratumMitigation flag ergonomically

Reviewed-by: shade, jbhateja

Author: olivergillespie

src/hotspot/cpu/x86/vm_version_x86.cpp

@@ -1069,6 +1069,7 @@ void VM_Version::get_processor_features() {
 
   if (FLAG_IS_DEFAULT(IntelJccErratumMitigation)) {
     _has_intel_jcc_erratum = compute_has_intel_jcc_erratum();
+    FLAG_SET_ERGO(IntelJccErratumMitigation, _has_intel_jcc_erratum);
   } else {
     _has_intel_jcc_erratum = IntelJccErratumMitigation;
   }