Kapt: add flag kapt.use.jvm.ir for enabling JVM IR support

#KT-49682

compiler/config.jvm/src/org/jetbrains/kotlin/config/JVMConfigurationKeys.java

@@ -85,11 +85,6 @@ public class JVMConfigurationKeys {
     public static final CompilerConfigurationKey<Boolean> IR =
             CompilerConfigurationKey.create("IR");
 
-    // Temporary option to make it possible to test kapt with JVM IR. As soon as all tests start to pass, it can be removed,
-    // and the backend (old or IR) will be deduced from the compiler arguments provided by the user.
-    public static final CompilerConfigurationKey<Boolean> USE_KAPT_WITH_JVM_IR =
-            CompilerConfigurationKey.create("Enable JVM IR for kapt");
-
     public static final CompilerConfigurationKey<Boolean> USE_PSI_CLASS_FILES_READING =
             CompilerConfigurationKey.create("use a slower (PSI-based) class files reading implementation");
 

compiler/ir/backend.jvm/entrypoint/src/org/jetbrains/kotlin/backend/jvm/JvmIrCodegenFactory.kt

@@ -203,10 +203,7 @@ open class JvmIrCodegenFactory(
         // We need to compile all files we reference in Klibs
         irModuleFragment.files.addAll(dependencies.flatMap { it.files })
 
-        if (!input.configuration.getBoolean(JVMConfigurationKeys.DO_NOT_CLEAR_BINDING_CONTEXT) && !input.configuration.getBoolean(
-                JVMConfigurationKeys.USE_KAPT_WITH_JVM_IR
-            )
-        ) {
+        if (!input.configuration.getBoolean(JVMConfigurationKeys.DO_NOT_CLEAR_BINDING_CONTEXT)) {
             val originalBindingContext = input.bindingContext as? CleanableBindingContext
                 ?: error("BindingContext should be cleanable in JVM IR to avoid leaking memory: ${input.bindingContext}")
             originalBindingContext.clear()

compiler/tests-compiler-utils/tests/org/jetbrains/kotlin/codegen/GenerationUtils.kt

@@ -187,8 +187,7 @@ object GenerationUtils {
         configureGenerationState: GenerationState.Builder.() -> Unit = {},
     ): GenerationState {
         val isIrBackend =
-            (classBuilderFactory.classBuilderMode == ClassBuilderMode.FULL && configuration.getBoolean(JVMConfigurationKeys.IR)) ||
-                    configuration.getBoolean(JVMConfigurationKeys.USE_KAPT_WITH_JVM_IR)
+            configuration.getBoolean(JVMConfigurationKeys.IR)
         val generationState = GenerationState.Builder(
             project, classBuilderFactory, analysisResult.moduleDescriptor, analysisResult.bindingContext,
             configuration