[5.9] Fix ManagedValue::isPlusOne for addresses

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• Explanation: Fix ManagedValue::isPlusOne for addresses.

  In some cases, SILGen would reuse an address value after it was
  consumed. This is incorrect according to SIL's memory
  rules. In-memory values cannot be reused after deinitialization.

  Change this API to return false for address values that don't have a
  cleanup and therefore cannot be destroyed.

• Scope of Issue: Before this fix, memory verification catches the
  incorrect SIL that SILGen produces for resilient enums that require
  a protocol conformance thunk for initialization. For example:

  public protocol ObjectProtocol {
  static func entityReference(_ id: EntityIdentifier) -> Self
  }

  public enum Object : ObjectProtocol {
  case entityReference(EntityIdentifier)
  }

  If we don't fix this, then SIL verification will continue to assert
  for real-world code. SIL verification is currently disabled by
  default for release compilers, but we rely on it for testing and
  triage.

• Risk: SILGen could potentially generate more copies, but they would
  be cheap copies. We don't know of any cases where this would be a
  problem. This was discused among the team and determined that we
  don't want to allow SILGen to perform optimizations where memory is
  reused after it is deinitialized. Performance improved after this
  change in many more benchmarks that it regressed.

• PR to main: Fix SILGen ManagedValue::isPlusOne for addresses #65579

• Reviewed By: Joe Groff and Michael Gottesman

• Resolves: rdar://108001491 (SIL verification failed: Found mutating or
  consuming use of an in_guaranteed parameter?!:
  !ImmutableAddressUseVerifier().isMutatingOrConsuming(fArg))

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@swift-ci test

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@tbkka @gottesmm If we're going to take this SILGen fix in 5.9 it's probably better sooner than later just for testing purposes. If there are any issues we can certainly revert.