FIR: report VAL_REASSIGNMENT on synthetic immutable properties

#KT-50972 Fixed

compiler/testData/diagnostics/tests/syntheticExtensions/javaProperties/FalseSetters.fir.kt

@@ -1,9 +1,9 @@
 // FILE: KotlinFile.kt
 fun foo(javaClass: JavaClass) {
-    javaClass.something1++
-    javaClass.something2++
-    javaClass.something3++
-    javaClass.something4++
+    javaClass.<!VAL_REASSIGNMENT!>something1<!>++
+    javaClass.<!VAL_REASSIGNMENT!>something2<!>++
+    javaClass.<!VAL_REASSIGNMENT!>something3<!>++
+    javaClass.<!VAL_REASSIGNMENT!>something4<!>++
     javaClass.something5 = null
 }
 

compiler/testData/diagnostics/tests/syntheticExtensions/javaProperties/Getter.fir.kt

@@ -6,7 +6,7 @@ class KotlinClass {
 fun foo(javaClass: JavaClass, kotlinClass: KotlinClass) {
     useInt(javaClass.getSomething())
     useInt(javaClass.something)
-    javaClass.something = 1
+    javaClass.<!VAL_REASSIGNMENT!>something<!> = 1
     javaClass.<!UNRESOLVED_REFERENCE!>Something<!>
     useInt(kotlinClass.getSomething())
     kotlinClass.<!UNRESOLVED_REFERENCE!>something<!>

compiler/testData/diagnostics/tests/syntheticExtensions/javaProperties/KotlinOverridesJava2.fir.kt

@@ -9,7 +9,7 @@ fun foo(k: KotlinClass) {
     if (<!SENSELESS_COMPARISON!>k.something == null<!>) return
 
     k.setSomething(1)
-    k.something = <!ASSIGNMENT_TYPE_MISMATCH!>1<!>
+    k.<!VAL_REASSIGNMENT!>something<!> = <!ASSIGNMENT_TYPE_MISMATCH!>1<!>
 }
 
 fun useString(i: String) {}