[klib tool] Add option to print ir

Dumping the IR from a klib is useful for debugging klib compilations.

^KT-58877

native/native.tests/testData/klibIr/fun.kt

@@ -0,0 +1,7 @@
+// FIR_IDENTICAL
+package test
+
+class A {
+    private fun foo() = 42
+    public fun bar(z: Int) = foo() + z
+}