llkd: do not crash kernel if llkd stops running

Today, assume llkd is not hardened enough to 100% guarantee that
lack of progress in inspection loops is a direct result of a
livelock condition affecting llkd itself.  Log a fatal alarm to
make init restart llkd instead for the time being.

ToDo: develop trust in llkd regarding sigalarm causes.

Test: compile
Bug: 119781757
Change-Id: I668dc1773898da6c95aad7221724b16f1684b067
diff --git a/llkd/libllkd.cpp b/llkd/libllkd.cpp
index 0827470..427dace 100644
--- a/llkd/libllkd.cpp
+++ b/llkd/libllkd.cpp
@@ -555,7 +555,9 @@
 }
 
 void llkAlarmHandler(int) {
-    llkPanicKernel(false, ::getpid(), "alarm");
+    LOG(FATAL) << "alarm";
+    // NOTREACHED
+    llkPanicKernel(true, ::getpid(), "alarm");
 }
 
 milliseconds GetUintProperty(const std::string& key, milliseconds def) {