FIR: report UNSAFE_CALL on dot when possible

compiler/fir/analysis-tests/testData/resolve/smartcasts/variables/delayedAssignment.kt

@@ -11,5 +11,5 @@ fun test(b: Boolean) {
     } else {
         a = null
     }
-    a.<!UNSAFE_CALL{LT}!><!UNSAFE_CALL{PSI}!>foo<!>()<!>
+    a<!UNSAFE_CALL!>.<!>foo()
 }

compiler/fir/analysis-tests/testData/resolve/smartcasts/variables/smartcastAfterReassignment.kt

@@ -18,5 +18,5 @@ fun test_3() {
     x = ""
     x.length
     x = null
-    x.<!UNSAFE_CALL!>length<!>
+    x<!UNSAFE_CALL!>.<!>length
 }