Test infra: refactor IGNORE_BACKEND directive

treat it as a general one, introduce *_K1 and *_K2 variants for
more specific ignoring

compiler/testData/codegen/bytecodeText/boxingOptimization/unsignedRangeIteratorSpecialization.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // WITH_STDLIB
 // IGNORE_BACKEND: JVM, JVM_IR
 // ^ TODO support new mangling rules in optimizer

compiler/testData/codegen/bytecodeText/constProperty/nonConstValHasNoDefaultValue_before.kt

@@ -1,7 +1,6 @@
 // TARGET_BACKEND: JVM
 // IGNORE_BACKEND: JVM_IR
 // ^ Disables a language feature introduced in 1.4. This test checks old backend's behavior and is needed as long as we support language version 1.3.
-// IGNORE_BACKEND_FIR: JVM_IR
 // FIR status: don't support legacy feature
 // !LANGUAGE: -NoConstantValueAttributeForNonConstVals
 

compiler/testData/codegen/bytecodeText/constants/byte.kt

@@ -1,5 +1,5 @@
 // LANGUAGE: -ApproximateIntegerLiteralTypesInReceiverPosition
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 // For reasons this test is ignored, go to KT-46419
 
 val a: Byte = 1 + 10

compiler/testData/codegen/bytecodeText/constants/short.kt

@@ -1,5 +1,5 @@
 // LANGUAGE: -ApproximateIntegerLiteralTypesInReceiverPosition
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 // For reasons this test is ignored, go to KT-46419
 
 val a: Short = 1 + 255

compiler/testData/codegen/bytecodeText/coroutines/debug/localVariableCorrectLabel.kt

@@ -21,4 +21,4 @@ suspend fun SequenceScope<Int>.awaitSeq(): Int = 42
 // 1 LINENUMBER 9 L18
 // 1 LOCALVARIABLE a I L[0-9]+ L18
 
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR

compiler/testData/codegen/bytecodeText/coroutines/varValueConflictsWithTable.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // This test checks, that different variables occupy the same slot
 // In JVM_IR, however, loop variable's lifetime goes beyond the loop itself, thus the test has no sense in JVM_IR
 // IGNORE_BACKEND: JVM_IR

compiler/testData/codegen/bytecodeText/falseSmartCast.kt

@@ -1,4 +1,4 @@
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 open class SuperFoo {
     public fun bar() {
         if (this is Foo) {

compiler/testData/codegen/bytecodeText/inlineClasses/delegatedPropertyMangling.kt

@@ -1,4 +1,4 @@
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 // LANGUAGE: +InlineClasses
 import kotlin.reflect.KProperty
 

compiler/testData/codegen/bytecodeText/inlineClasses/mangledInlineClassInterfaceImplementation.kt

@@ -1,5 +1,5 @@
 // !LANGUAGE: +InlineClasses
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 
 interface A<T> {
     fun foo(a: T): String

compiler/testData/codegen/bytecodeText/inlineClasses/resultApiRunCatchingDoesntBox.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // IGNORE_BACKEND: JVM
 // IGNORE_BACKEND: JVM_IR
 // WITH_STDLIB

compiler/testData/codegen/bytecodeText/intrinsicsCompare/shortSmartCast_after.kt

@@ -1,5 +1,4 @@
 // !LANGUAGE: +ProperIeee754Comparisons
-// IGNORE_BACKEND_FIR: JVM_IR
 // IGNORE_BACKEND: JVM_IR
 
 fun equals3(a: Short?, b: Short?) = a != null && b != null && a == b

compiler/testData/codegen/bytecodeText/intrinsicsCompare/shortSmartCast_before.kt

@@ -1,5 +1,4 @@
 // !LANGUAGE: -ProperIeee754Comparisons
-// IGNORE_BACKEND_FIR: JVM_IR
 // IGNORE_BACKEND: JVM_IR
 
 fun equals3(a: Short?, b: Short?) = a != null && b != null && a == b

compiler/testData/codegen/bytecodeText/javaStatics.kt

@@ -1,4 +1,4 @@
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 // FILE: Child.java
 
 class Child extends Parent {

compiler/testData/codegen/bytecodeText/when/exhaustiveWhenSpecialCases.kt

@@ -1,4 +1,4 @@
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 
 enum class A { V1 }
 

compiler/testData/codegen/bytecodeText/when/exhaustiveWhenUnitStatement.kt

@@ -1,4 +1,4 @@
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 
 enum class AccessMode { READ, WRITE, EXECUTE }
 

compiler/testData/codegen/bytecodeText/whenEnumOptimization/nestedWhenInCondition.kt

@@ -1,4 +1,4 @@
-// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
 // FIR_STATUS: FIR+JVM_IR generates TABLESWITCH for nested 'when' only, doesn't look critical.
 
 // JVM_IR_TEMPLATES