[K/N] Fixed a problem with built coroutine visibility

#KT-55494 Fixed

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

@@ -221,7 +221,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
                 endOffset = irFunction.endOffset
                 origin = DECLARATION_ORIGIN_COROUTINE_IMPL
                 name = nameForCoroutineClass(irFunction)
-                visibility = irFunction.visibility
+                visibility = DescriptorVisibilities.PRIVATE
             }.apply {
                 parent = irFunction.parent
                 createParameterDeclarations()

kotlin-native/backend.native/tests/filecheck/suspend_returnNothing.kt

@@ -16,7 +16,7 @@ open class EmptyContinuation(override val context: CoroutineContext = EmptyCorou
 suspend fun suspendForever(): Int = suspendCoroutineUninterceptedOrReturn {
     COROUTINE_SUSPENDED
 }
-// CHECK-LABEL: define %struct.ObjHeader* @"kfun:$fooCOROUTINE
+// CHECK-LABEL: define internal %struct.ObjHeader* @"kfun:$fooCOROUTINE
 
 // CHECK-NOT: ; Function Attrs: {{.*}}noreturn
 // CHECK-LABEL: define %struct.ObjHeader* @"kfun:#foo#suspend(kotlin.coroutines.Continuation<kotlin.Nothing>){}kotlin.Any"

kotlin-native/backend.native/tests/filecheck/suspend_tailcalls.kt

@@ -281,7 +281,7 @@ suspend fun s23(f: Boolean) {
 
 // CHECK-LABEL: define %struct.ObjHeader* @"kfun:#s24#suspend(kotlin.coroutines.Continuation<kotlin.Unit>){}kotlin.Any
 suspend fun s24() {
-    // CHECK: call void @"kfun:$s24COROUTINE${{[0-9]*}}#<init>
+    // CHECK: call void @"kfun:$s24COROUTINE${{[0-9]*}}.<init>#internal
     sInt()
 }
 // CHECK-LABEL: epilogue: