JVM IR: (Un)mute tests and add more tests for bridge generation

compiler/testData/codegen/box/smartCasts/falseSmartCast.kt

@@ -1,3 +1,5 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+
 open class SuperFoo {
     public fun bar(): String {
         if (this is Foo) {
@@ -14,4 +16,4 @@ class Foo : SuperFoo() {
     public fun superFoo() {}
 }
 
-fun box(): String = Foo().bar()
+fun box(): String = Foo().bar()

compiler/testData/codegen/box/smartCasts/implicitReceiverInWhen.kt

@@ -1,3 +1,5 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+
 open class A {
     fun f(): String =
             when (this) {