liquidio: lowmem: init allocated memory to 0

For defensive programming, zero the allocated block 'oct->droq[0]' in
octeon_setup_output_queues() and 'oct->instr_queue[0]' in
octeon_setup_instr_queues().

Signed-off-by: Rick Farrington <ricardo.farrington@cavium.com>
Signed-off-by: Satanand Burla <satananda.burla@cavium.com>
Signed-off-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>