Remove obsolete @OptIn(ExperimentalUnsignedTypes::class) annotations

^KT-62510

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/ConeIntegerLiteralTypeImpl.kt

@@ -34,7 +34,6 @@ class ConeIntegerLiteralConstantTypeImpl(
         return getApproximatedTypeImpl(expectedType)
     }
 
-    @OptIn(ExperimentalUnsignedTypes::class)
     companion object {
         fun create(
             value: Long,

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ProgressionType.kt

@@ -3,7 +3,6 @@
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
-@file:OptIn(ExperimentalUnsignedTypes::class)
 
 package org.jetbrains.kotlin.backend.common.lower.loops