Everywhere: Use nothrow new with adopt_{ref,own}_if_nonnull

This commit converts naked `new`s to `AK::try_make` and `AK::try_create`
wherever possible. If the called constructor is private, this can not be
done, so we instead now use the standard-defined and compiler-agnostic
`new (nothrow)`.

Kernel/FileSystem/InodeWatcher.cpp

@@ -14,7 +14,7 @@ namespace Kernel {
 
 KResultOr<NonnullRefPtr<InodeWatcher>> InodeWatcher::create()
 {
-    auto watcher = adopt_ref_if_nonnull(new InodeWatcher);
+    auto watcher = adopt_ref_if_nonnull(new (nothrow) InodeWatcher);
     if (watcher)
         return watcher.release_nonnull();
     return ENOMEM;