CLI: remove obsolete -Xdump-declarations-to

It was only used in the very old version of binary compatibility
validator. It was never supported in the JVM IR backend.

compiler/tests-common/tests/org/jetbrains/kotlin/codegen/AbstractDumpDeclarationsTest.kt

@@ -1,29 +0,0 @@
-/*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.codegen
-
-import org.jetbrains.kotlin.config.CompilerConfiguration
-import org.jetbrains.kotlin.config.JVMConfigurationKeys
-import org.jetbrains.kotlin.test.KotlinTestUtils
-import java.io.File
-
-abstract class AbstractDumpDeclarationsTest : CodegenTestCase() {
-
-    private lateinit var dumpToFile: File
-
-    override fun doMultiFileTest(wholeFile: File, files: List<TestFile>) {
-        val expectedResult = KotlinTestUtils.replaceExtension(wholeFile, "json")
-        dumpToFile = KotlinTestUtils.tmpDirForTest(this).resolve("$name.json")
-        compile(files)
-        classFileFactory.generationState.destroy()
-        KotlinTestUtils.assertEqualsToFile(expectedResult, dumpToFile.readText())
-    }
-
-    override fun updateConfiguration(configuration: CompilerConfiguration) {
-        super.updateConfiguration(configuration)
-        configuration.put(JVMConfigurationKeys.DECLARATIONS_JSON_PATH, dumpToFile.path)
-    }
-}