ART: Remove LogSeverity NONE

Remove non-standard severity, and instead use a new enum to
configure verifier logging.

Partially reverts commit 7fe30233d32a872f5349e921dba65bd767ad994b.

Bug: 31338270
Test: m test-art-host
Change-Id: If52ee23c4902fbf2dabe7b232f6742448764ff8c
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 8edb1b4..4d252e1 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -3848,7 +3848,9 @@
   return false;
 }
 
-void ClassLinker::VerifyClass(Thread* self, Handle<mirror::Class> klass, LogSeverity log_level) {
+void ClassLinker::VerifyClass(Thread* self,
+                              Handle<mirror::Class> klass,
+                              verifier::HardFailLogMode log_level) {
   {
     // TODO: assert that the monitor on the Class is held
     ObjectLock<mirror::Class> lock(self, klass);