FIR CFG: merge data flow if called-in-place lambda may not be called

compiler/tests-spec/testData/diagnostics/notLinked/contracts/analysis/smartcasts/pos/12.fir.kt

@@ -10,7 +10,7 @@ fun case_1(arg: Int?) {
 // TESTCASE NUMBER: 2
 fun case_2(arg: Int?) {
     funWithAtLeastOnceCallsInPlace { arg!! }
-    arg<!UNSAFE_CALL!>.<!>inc()
+    arg.inc()
 }
 
 // TESTCASE NUMBER: 3
@@ -24,5 +24,5 @@ fun case_3() {
 fun case_4() {
     val value_1: Boolean?
     funWithAtLeastOnceCallsInPlace { <!VAL_REASSIGNMENT!>value_1<!> = true }
-    value_1<!UNSAFE_CALL!>.<!>not()
+    value_1.not()
 }