IB/ehca: Use round_jiffies() for EQ polling timer

Use round_jiffies() to align ehca's 1-second timer with other timers
and potentially save power by sleeping cores for longer.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>