Drivers: hv: vmbus: Add comments about races with "channels" sysfs dir

The VMBus driver code has some inherent races in the creation of the
"channels" sysfs subdirectory and its per-channel numbered subdirectories.
These races have not generally been recognized or understood. Add some
comments to call them out. No code changes.

Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20250514225508.52629-1-mhklinux@outlook.com


Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20250514225508.52629-1-mhklinux@outlook.com>