Kapt: handle special names correctly

Parameter names of some methods are different in JVM IR, for example
extension receivers of property `$annotations` methods are named
`<this>`, which made the `Name.identifier` call fail. It seems fine to
use the "p + index" name for this instead.

 #KT-49682

plugins/kapt3/kapt3-compiler/testData/converter/annotations2_ir.txt

@@ -27,19 +27,19 @@ public final class AnnotationsTest {
     @Anno(value = "top-level-fun")
     public static final void topLevelFun(@org.jetbrains.annotations.NotNull()
     @Anno(value = "top-level-fun-receiver")
-    java.lang.String $this$topLevelFun) {
+    java.lang.String p0) {
+    }
+
+    @org.jetbrains.annotations.NotNull()
+    public static final java.lang.String getTopLevelVal(@Anno(value = "top-level-val-receiver")
+    int p0) {
+        return null;
     }
 
     @Anno(value = "top-level-val")
     @java.lang.Deprecated()
     public static void getTopLevelVal$annotations(int p0) {
     }
-
-    @org.jetbrains.annotations.NotNull()
-    public static final java.lang.String getTopLevelVal(@Anno(value = "top-level-val-receiver")
-    int $this$topLevelVal) {
-        return null;
-    }
 }
 
 ////////////////////

plugins/kapt3/kapt3-compiler/testData/converter/implicitReturnTypes.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // WITH_STDLIB
 
 // FILE: lib/Prop.java