misc: vmw_vmci: Switch to kvfree_rcu() API

Instead of invoking a synchronize_rcu() to free a pointer
after a grace period we can directly make use of new API
that does the same but in more efficient way.

Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Link: https://lore.kernel.org/r/20211215111845.2514-6-urezki@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>