[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/nullableDoubleEquals10.kt

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun myEquals(a: Double?, b: Double?) = a == b
 

compiler/testData/codegen/bytecodeText/ieee754/oldLanguageVersions/nullableDoubleNotEquals10.kt

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun myNotEquals(a: Double?, b: Double?) = a != b
 

compiler/testData/codegen/bytecodeText/ieee754/oldLanguageVersions/nullableFloatEquals10.kt

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun myEquals(a: Float?, b: Float?) = a == b
 

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

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun myNotEquals(a: Float?, b: Float?) = a != b
 

compiler/testData/codegen/bytecodeText/ieee754/oldLanguageVersions/smartCastsForDouble10.kt

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun equals5(a: Any?, b: Any?) = if (a is Double && b is Double?) a == b else null!!
 

compiler/testData/codegen/bytecodeText/ieee754/oldLanguageVersions/smartCastsForFloat10.kt

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun equals5(a: Any?, b: Any?) = if (a is Float && b is Float?) a == b else null!!
 

compiler/testData/codegen/bytecodeText/ieee754/oldLanguageVersions/when10.kt

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun box(): String {
     val plusZero: Any = 0.0

compiler/testData/codegen/bytecodeText/ieee754/oldLanguageVersions/whenNullableSmartCast10.kt

@@ -1,5 +1,4 @@
 // !API_VERSION: 1.0
-// IGNORE_BACKEND: JVM_IR
 
 fun box(): String {
     val nullValue: Any? = null