Break out bytecodeText/conditions tests into smaller tests for if/while/do-while.

compiler/testData/codegen/bytecodeText/conditions/negatedNullCompareInWhile.kt

@@ -0,0 +1,18 @@
+fun main(p: String?, p2: String?) {
+    // Generates IFNULL and GOTO
+    while (!(p == null)) {
+        "loop"
+    }
+
+    // Generates IFNULL and GOTO
+    while (p2 != null) {
+        "loop"
+    }
+}
+
+//0 ICONST_0
+//0 ICONST_1
+//0 ACONST_NULL
+//2 IFNULL
+//2 IF
+//2 GOTO