[Backend] Reorganize version 1.0 codegen tests

- Extract all backend codegen tests that specifically target behaviour
  in to-be-deprecated functionality from language versions < 1.3"
- Remove those tests from the JVM IR test suite.

compiler/testData/codegen/bytecodeText/ieee754/oldLanguageVersions/nullableFloatNotEquals10.kt

@@ -0,0 +1,29 @@
+// !API_VERSION: 1.0
+
+fun myNotEquals(a: Float?, b: Float?) = a != b
+
+fun myNotEquals1(a: Float?, b: Float) = a != b
+
+fun myNotEquals2(a: Float, b: Float?) = a != b
+
+fun myNotEquals0(a: Float, b: Float) = a != b
+
+
+fun box(): String {
+    if (myNotEquals(null, null)) return "fail 1"
+    if (!myNotEquals(null, 0.0F)) return "fail 2"
+    if (!myNotEquals(0.0F, null)) return "fail 3"
+    if (myNotEquals(0.0F, 0.0F)) return "fail 4"
+
+    if (!myNotEquals1(null, 0.0F)) return "fail 5"
+    if (myNotEquals1(0.0F, 0.0F)) return "fail 6"
+
+    if (!myNotEquals2(0.0F, null)) return "fail 7"
+    if (myNotEquals2(0.0F, 0.0F)) return "fail 8"
+
+    if (myNotEquals0(0.0F, 0.0F)) return "fail 9"
+
+    return "OK"
+}
+
+// 0 areEqual