pds_core: check health in devcmd wait

Similar to what we do in the AdminQ, check for devcmd health
while waiting for an answer.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>