[Fir2IR] Get rid of simple symbol table usages

We have two sources of truth in Fir2Ir - declaration storages,
which maps fir to ir symbols and symbolTable which maps
IdSignature to ir symbol.

The long-term goal is to have only one - declaration storages. This
commit goes to this goal by removing all symbolTable usages that are
straightforward to remove, i.e., all except:

1. classes as there is some code, that uses signature inside ClassSymbol
2. functions/properties as sometimes declaration storage fails to match
symbols correctly (i.e. for generated data class members)
3. type parameters, as we need to remove functions first.

As a side effect, it fixes some of the signature clash cases on valid
code, as we no longer rely on signature uniqueness, except cases
mentioned above.

^KT-65274 Fixed
^KT-64990

compiler/testData/codegen/box/fakeOverride/kt65274.kt

@@ -0,0 +1,20 @@
+// TARGET_BACKEND: JVM
+
+// FILE: a/A.java
+package a;
+
+public class A {
+    static final String X = "Fail";
+}
+
+// FILE: B.java
+public class B extends a.A {
+    private final String X = "OK";
+
+    public String get() { return X; }
+}
+
+// FILE: box.kt
+class C : B()
+
+fun box(): String = C().get()