[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/smartCasts/loops/safeCallInsideDoWhile.fir.kt

@@ -0,0 +1,12 @@
+fun foo(x: String): String? = x
+
+fun calc(x: String?): Int {
+    do {
+        // Smart cast because of x!! in receiver
+        foo(x!!)?.subSequence(0, x.length)
+        // Smart cast because of x!! in receiver
+        if (x.length == 0) break
+    } while (true)
+    // Here x is also not null
+    return x.length
+}