[LL FIR] do not crash on attempt to resolve class initializer in case of class clash

^KT-61788 Fixed

analysis/low-level-api-fir/testData/getOrBuildFir/declarations/initializerConflict.kt

@@ -0,0 +1,11 @@
+// LOOK_UP_FOR_ELEMENT_OF_TYPE: org.jetbrains.kotlin.psi.KtClassInitializer
+
+package one.two
+
+class A
+typealias Foo = A
+class Foo {
+    <expr>init {
+        val i = 1
+    }</expr>
+}