[FIR2IR] Use only data class primary constructor parameters for equals

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/generators/DataClassMembersGenerator.kt

@@ -119,7 +119,11 @@ class DataClassMembersGenerator(val components: Fir2IrComponents) {
                     (this.name == toStringName && matchesToStringSignature)
 
         fun generate(klass: FirClass<*>): List<Name> {
-            val properties = irClass.declarations.filterIsInstance<IrProperty>().map { it.descriptor }
+            val propertyParametersCount = irClass.primaryConstructor?.explicitParameters?.size ?: 0
+            val properties = irClass.declarations
+                .filterIsInstance<IrProperty>()
+                .take(propertyParametersCount)
+                .map { it.descriptor }
             if (properties.isEmpty()) {
                 return emptyList()
             }

compiler/testData/codegen/box/secondaryConstructors/dataClasses.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 internal data class A1(val prop1: String) {
     val prop2: String = "const2"
     var prop3: String = ""