Elvis DFA: now only left part is taken into account #KT-9100 Fixed

I had to fix a few incorrect tests using something like x!! in Elvis right part, and also one bug in our code

compiler/testData/diagnostics/tests/smartCasts/elvisExclExclPlatform.txt

@@ -0,0 +1,16 @@
+package
+
+package p {
+    public fun bar(/*0*/ x: kotlin.String): kotlin.String
+    public fun test(/*0*/ x: kotlin.String?): kotlin.Any
+
+    public/*package*/ open class My {
+        public/*package*/ constructor My()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+        // Static members
+        org.jetbrains.annotations.Nullable() public/*package*/ open fun create(): kotlin.String?
+    }
+}