Do not remove dead variables' LVT records

Also, extend liveness of alive variable to nearest suspension points
 #KT-44714

compiler/testData/checkLocalVariablesTable/suspendFunctionDeadVariables.kt

@@ -0,0 +1,14 @@
+// WITH_RUNTIME
+
+suspend fun dummy() {}
+
+suspend fun test() {
+    dummy()
+    val a = 0
+}
+
+// METHOD : SuspendFunctionDeadVariablesKt.test(Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
+
+// VARIABLE : NAME=a TYPE=I INDEX=1
+// VARIABLE : NAME=$continuation TYPE=Lkotlin/coroutines/Continuation; INDEX=3
+// VARIABLE : NAME=$result TYPE=Ljava/lang/Object; INDEX=2