CLI: improve error message for -Xjdk-release=1.6/1.7

#KT-66174 Fixed

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/jvmArguments.kt

@@ -43,10 +43,12 @@ fun CompilerConfiguration.setupJvmSpecificArguments(arguments: K2JVMCompilerArgu
                 put(JVMConfigurationKeys.JDK_RELEASE, value)
             }
             if (jvmTargetArg != null && !isCompatibleJvmTargetAndRelease(jvmTargetArg, releaseTargetArg)) {
+                val suggestion =
+                    if (value < 8) "Please change the value of the 'jvm-target' option to 1.8"
+                    else "Please remove the '-jvm-target' option"
                 messageCollector.report(
                     ERROR,
-                    "'-Xjdk-release=$releaseTargetArg' option conflicts with '-jvm-target $jvmTargetArg'. " +
+                    "'-Xjdk-release=$releaseTargetArg' option conflicts with '-jvm-target $jvmTargetArg'. $suggestion"
-                            "Please remove the '-jvm-target' option"
                 )
             }
         }
@@ -57,7 +59,8 @@ fun CompilerConfiguration.setupJvmSpecificArguments(arguments: K2JVMCompilerArgu
             if (jvmTargetArg == null) {
                 messageCollector.report(
                     ERROR,
-                    "'-Xjdk-release=$releaseTargetArg' option requires explicit JVM target. Please specify the '-jvm-target' option"
+                    "'-Xjdk-release=$releaseTargetArg' option requires JVM target explicitly set to 1.8. " +
+                            "Please specify the '-jvm-target' option"
                 )
             }
             jvmTargetArg

compiler/testData/cli/jvm/jdkRelease6WithJvmTarget9.args

@@ -0,0 +1,8 @@
+-Xjdk-release=1.6
+-jvm-target
+9
+-jdk-home
+$JDK_11_0
+$TESTDATA_DIR$/jdkRelease.kt
+-d
+$TEMP_DIR$

compiler/testData/cli/jvm/jdkRelease6WithJvmTarget9.out

@@ -0,0 +1,2 @@
+error: '-Xjdk-release=1.6' option conflicts with '-jvm-target 9'. Please change the value of the 'jvm-target' option to 1.8
+COMPILATION_ERROR

compiler/testData/cli/jvm/jdkRelease6WithoutExplicitJvmTarget.out

@@ -1,2 +1,2 @@
-error: '-Xjdk-release=1.6' option requires explicit JVM target. Please specify the '-jvm-target' option
+error: '-Xjdk-release=1.6' option requires JVM target explicitly set to 1.8. Please specify the '-jvm-target' option
 COMPILATION_ERROR

compiler/tests-gen/org/jetbrains/kotlin/cli/CliTestGenerated.java

@@ -775,6 +775,11 @@ public class CliTestGenerated extends AbstractCliTest {
       runTest("compiler/testData/cli/jvm/jdkRelease6WithJvmTarget8Jdk8.args");
     }
 
+    @TestMetadata("jdkRelease6WithJvmTarget9.args")
+    public void testJdkRelease6WithJvmTarget9() {
+      runTest("compiler/testData/cli/jvm/jdkRelease6WithJvmTarget9.args");
+    }
+
     @TestMetadata("jdkRelease6WithoutExplicitJvmTarget.args")
     public void testJdkRelease6WithoutExplicitJvmTarget() {
       runTest("compiler/testData/cli/jvm/jdkRelease6WithoutExplicitJvmTarget.args");