JVM IR: generate private @JvmStatic functions as in old backend

#KT-46181 Fixed

compiler/testData/codegen/bytecodeListing/jvmStatic/jvmStaticPrivate.kt

@@ -0,0 +1,35 @@
+// WITH_RUNTIME
+
+// For a private @JvmStatic function `f` in `A.Companion`, we generate:
+// 1) private instance method `f` in `A.Companion`, with the actual implementation;
+// 2) public static method `access$f` in `A.Companion` which calls `A.Companion.f`;
+// 3) private static method `f` in `A` which calls `A.Companion.access$f`.
+// (which is basically the same as all @JvmStatic companion functions, except that we also need an accessor here.)
+//
+// This might seem like an overkill, but there are actually some use cases, namely private static helpers for JNI (see KT-46181).
+
+class A {
+    companion object {
+        @JvmStatic
+        private fun f(p: Int) {}
+
+        @JvmStatic
+        private val x = ""
+
+        private var xx: String
+            @JvmStatic get() = ""
+            @JvmStatic set(value) {}
+    }
+}
+
+object O {
+    @JvmStatic
+    private fun g(q: Int) {}
+
+    @JvmStatic
+    private val y = ""
+
+    private var yy: String
+        @JvmStatic get() = ""
+        @JvmStatic set(value) {}
+}