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/cli/cli-common/gen/org/jetbrains/kotlin/cli/common/arguments/K2JVMCompilerArgumentsCopyGenerated.kt

@@ -19,7 +19,6 @@ fun copyK2JVMCompilerArguments(from: K2JVMCompilerArguments, to: K2JVMCompilerAr
     to.buildFile = from.buildFile
     to.classpath = from.classpath
     to.compileJava = from.compileJava
-    to.declarationsOutputPath = from.declarationsOutputPath
     to.defaultScriptExtension = from.defaultScriptExtension
     to.destination = from.destination
     to.disableStandardScript = from.disableStandardScript

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/K2JVMCompilerArguments.kt

@@ -313,17 +313,6 @@ This can be used in the event of problems with the new implementation."""
             field = value
         }
 
-    @Argument(
-        value = "-Xdump-declarations-to",
-        valueDescription = "<path>",
-        description = "Path to the JSON file where Java-to-Kotlin declaration mappings should be dumped."
-    )
-    var declarationsOutputPath: String? = null
-        set(value) {
-            checkFrozen()
-            field = if (value.isNullOrEmpty()) null else value
-        }
-
     @Argument(
         value = "-Xsuppress-missing-builtins-error",
         description = """Suppress the "cannot access built-in declaration" error (useful with '-no-stdlib')."""