Move another LOG to VLOG(signals)

Bug: 15024631
Change-Id: I5ef79292a69fe268fa52663731a38cfb3b856f32
diff --git a/runtime/fault_handler.cc b/runtime/fault_handler.cc
index 4d7fd0a..8d750c5 100644
--- a/runtime/fault_handler.cc
+++ b/runtime/fault_handler.cc
@@ -79,7 +79,7 @@
       return;
     }
   }
-  LOG(ERROR)<< "Caught unknown SIGSEGV in ART fault handler";
+  VLOG(signals)<< "Caught unknown SIGSEGV in ART fault handler";
   oldaction_.sa_sigaction(sig, info, context);
 }