assert(ctrl != __null) failed: control out is assumed to be unique after JDK-8281732

The following tests fail after JDK-8281732.

```
compiler/gcbarriers/UnsafeIntrinsicsTest.java
gc/metaspace/TestMetaspacePerfCounters.java
gc/shenandoah/TestEvilSyncBug.java
gc/stringdedup/TestStringDeduplicationFullGC.java
gc/stringdedup/TestStringDeduplicationTableResize.java
gc/stringdedup/TestStringDeduplicationYoungGC.java
serviceability/dcmd/gc/HeapDumpCompressedTest.java
jdk/jfr/event/gc/detailed/TestGCPhaseConcurrent.java
jdk/jfr/event/gc/detailed/TestShenandoahHeapRegionStateChangeEvent.java
jdk/jfr/event/gc/detailed/TestShenandoahHeapRegionInformationEvent.java
jdk/jfr/event/oldobject/TestShenandoah.java
sun/net/www/protocol/https/HttpsURLConnection/B6216082.java
sun/tools/jmap/BasicJMapTest.java
```

```
#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/workspace/jdk/src/hotspot/share/opto/node.cpp:2410), pid=157605, tid=157722
# assert(ctrl != __null) failed: control out is assumed to be unique
#
# JRE version: OpenJDK Runtime Environment (19.0) (fastdebug build 19-internal-adhoc..jdk)
# Java VM: OpenJDK 64-Bit Server VM (fastdebug 19-internal-adhoc..jdk, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, shenandoah gc, li
nux-amd64)
# Problematic frame:
# V [libjvm.so+0x1399587] Node::unique_ctrl_out() const+0x87
```