[IR] Don't print multifile/synthetic facade class names in irText tests

This only applies to JVM and fq-names in declaration references
in IR dumps.

This enables us to run more irText tests on platforms other than JVM
(see KT-58605).

compiler/testData/ir/irText/declarations/contextReceivers/function.sig.kt.txt

@@ -10,6 +10,9 @@ class C {
     // CHECK JVM_IR:
     //   Mangled name: C#<get-c>(){}kotlin.Int
     //   Public signature: /C.c.<get-c>|-2440337234483931882[0]
+    // CHECK JS_IR NATIVE:
+    //   Mangled name: C#<get-c>(){}
+    //   Public signature: /C.c.<get-c>|2368736057102379596[0]
     get
 
   // CHECK: