liquidio: replace info-pointer mode with buffer-pointer-only mode

Each Octeon output ring can DMA packets to host memory in two modes:  info-
pointer mode and buffer-pointer-only mode.  In info-pointer mode, Octeon
takes two buffer pointers for each packet and places the length of the
packet along with specified number of bytes from the beginning of the
packet into one buffer and the rest of the packet in a separate buffer.  In
buffer-pointer-only mode, Octeon takes single buffer pointer and places the
length of the packet at the beginning of the buffer followed by the packet
data.

This patch switches all Octeon output rings from info-pointer mode to
buffer-pointer-only mode.  This results in fewer DMA setups and cache line
snoops.

Signed-off-by: Prasad Kanneganti <pkanneganti@cavium.com>
Signed-off-by: Derek Chickles <derek.chickles@cavium.com>
Signed-off-by: Satanand Burla <satananda.burla@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>