FIR: Use Any? expect type to the argument list of ==

^KT-47409 Related

compiler/fir/analysis-tests/testData/resolve/inference/equals.fir.txt

@@ -0,0 +1,18 @@
+FILE: equals.kt
+    public final fun <T> materialize(): R|T| {
+        ^materialize R|kotlin/TODO|()
+    }
+    public final fun main(): R|kotlin/Unit| {
+        when () {
+            ==(String(), R|/materialize|<R|kotlin/Any?|>()) ->  {
+                ^main Unit
+            }
+        }
+
+        when () {
+            ==(R|/materialize|<R|kotlin/Any?|>(), String()) ->  {
+                ^main Unit
+            }
+        }
+
+    }

compiler/fir/analysis-tests/testData/resolve/inference/equals.kt

@@ -0,0 +1,6 @@
+fun <T> materialize(): T = TODO()
+
+fun main() {
+    if ("" == materialize()) return // FE1.0: OK, type argument inferred to Any?
+    if (materialize() == "") return // FE1.0: Error, uninferred type argument for `T`
+}