Fix J9ClassHasIdentity flag assignment

[AditiS11]

Set the J9ClassHasIdentity flag only if the class is
not a value class and not an interface.

Fixes the following failure in test/jdk/valhalla/valuetypes/ValueClassTest.java

[14:01:06.476] STARTED    ValueClassTest::testIsValueObjectCompatible 'testIsValueObjectCompatible()'
org.opentest4j.AssertionFailedError: interface: java.lang.Comparable ==> expected: <true> but was: <false>
	at org.junit.jupiter.api.AssertionFailureBuilder.build(AssertionFailureBuilder.java:151)
	at org.junit.jupiter.api.AssertionFailureBuilder.buildAndThrow(AssertionFailureBuilder.java:132)
	at org.junit.jupiter.api.AssertEquals.failNotEqual(AssertEquals.java:197)
	at org.junit.jupiter.api.AssertEquals.assertEquals(AssertEquals.java:188)
	at org.junit.jupiter.api.Assertions.assertEquals(Assertions.java:1167)
	at ValueClassTest.isValueObjectCompatibleCase(ValueClassTest.java:63)
	at ValueClassTest.testIsValueObjectCompatible(ValueClassTest.java:51)
	at java.base/java.lang.reflect.Method.invoke(Method.java:571)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1604)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1604)

[theresa-m]

I think you can remove the interface check here. J9ROMCLASS_IS_VALUE is only true when an interface flag is not set.

[AditiS11]

J9ROMCLASS_IS_VALUE is false for interfaces. If I remove the interface check, J9ROMCLASS_IS_VALUE will return false for interfaces and enters the else if block and sets J9ClassHasIdentity flag for interfaces too.

[hangshao0]

Jenkins test sanity.functional,extended plinuxval jdknext

[hangshao0]

Jenkins compile amac jdk21

[theresa-m]

@AditiS11 please open a pull request to remove ValueClassTest from https://github.com/adoptium/aqa-tests/blob/master/openjdk/excludes/ProblemList_openjdkvalhalla-openj9.txt.