[FIR] Render integer literal types as Int in diagnostic messages

#KT-55662 Fixed

compiler/testData/diagnostics/tests/PropertyInitializers.fir.kt

@@ -0,0 +1,13 @@
+// WITH_STDLIB
+
+class Foo(val a: Int, b: Int) {
+    val c = a + b
+
+    val d: Int
+        get() = a
+
+    val e: Int
+        get() = <!UNRESOLVED_REFERENCE!>b<!>
+
+    val map: Map<String, Int> = <!INITIALIZER_TYPE_MISMATCH, TYPE_MISMATCH("kotlin/String; kotlin/Int"), TYPE_MISMATCH("kotlin/String; kotlin/Int"), TYPE_MISMATCH("kotlin/Int; kotlin/String"), TYPE_MISMATCH("kotlin/String; kotlin/Int"), TYPE_MISMATCH("kotlin/Int; kotlin/String")!>mapOf(1 to "hello")<!>
+}