FIR: add UnsafeCall resolution diagnostics

Previously unsafe call is reported as part of InapplicableWrongReceiver.
This makes it difficult for the downstream checkers to report different
diagnostics.

compiler/testData/diagnostics/tests/resolve/invoke/invokeAndSmartCast.fir.kt

@@ -12,7 +12,7 @@ fun test(a: A) {
 
     with("") {
         a.x(<!NO_VALUE_FOR_PARAMETER!>)<!>
-        (a.x)(<!NO_VALUE_FOR_PARAMETER!>)<!>
+        <!UNSAFE_IMPLICIT_INVOKE_CALL!>(a.x)<!>()
         if (a.x != null) {
             a.x(<!NO_VALUE_FOR_PARAMETER!>)<!> // todo
             (a.x)()