AK: Export adopt_nonnull_ref_or_enomem to the global namespace

Author: https://github.com/AtkinsSJ
Commit: https://github.com/SerenityOS/serenity/commit/6e0ad5536f
Pull-request: https://github.com/SerenityOS/serenity/pull/16851
Reviewed-by: https://github.com/linusg
Reviewed-by: https://github.com/trflynn89 ✅

AK/RefPtr.h

@@ -353,6 +353,7 @@ inline ErrorOr<NonnullRefPtr<T>> adopt_nonnull_ref_or_enomem(T* object)
 }
 
 #if USING_AK_GLOBALLY
+using AK::adopt_nonnull_ref_or_enomem;
 using AK::adopt_ref_if_nonnull;
 using AK::RefPtr;
 using AK::static_ptr_cast;