[FIR] Quick fix FirModifierChecker

core/compiler.common/src/org/jetbrains/kotlin/descriptors/annotations/KotlinTarget.kt

@@ -56,6 +56,8 @@ enum class KotlinTarget(val description: String, val isDefault: Boolean = true)
     TOP_LEVEL_PROPERTY_WITH_DELEGATE("top level property with delegate", false),
     TOP_LEVEL_PROPERTY_WITHOUT_FIELD_OR_DELEGATE("top level property without backing field or delegate", false),
 
+    BACKING_FIELD("backing field"),
+
     INITIALIZER("initializer", false),
     DESTRUCTURING_DECLARATION("destructuring declaration", false),
     LAMBDA_EXPRESSION("lambda expression", false),

core/compiler.common/src/org/jetbrains/kotlin/resolve/AnnotationTargetLists.kt

@@ -54,6 +54,7 @@ object AnnotationTargetLists {
 
     val T_PROPERTY_GETTER = targetList(PROPERTY_GETTER)
     val T_PROPERTY_SETTER = targetList(PROPERTY_SETTER)
+    val T_BACKING_FIELD = targetList(BACKING_FIELD)
 
     val T_VALUE_PARAMETER_WITHOUT_VAL = targetList(VALUE_PARAMETER)