liquidio: make timeout HZ independent and readable

schedule_timeout_* takes a timeout in jiffies but the code currently is
passing in a constant which makes this timeout HZ dependent. So define
a constant with (hopefully) meaningful name and pass it through
msecs_to_jiffies() to fix the HZ dependency.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
commit f21fb3ed ("Add support of Cavium Liquidio ethernet adapters")
Acked-by: Derek Chickles <derek.chickles@caviumnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>