Use kzalloc rather than duplicating its implementation, which
makes code simple and easy to understand.
Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Link: https://lore.kernel.org/r/1650277333-31090-1-git-send-email-baihaowen@meizu.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>