bnx2x: Assign unique DMAE channel number for FW DMAE transactions.

Driver assigns DMAE channel 0 for FW as part of START_RAMROD command. FW
uses this channel for DMAE operations (e.g., TIME_SYNC implementation).
Driver also uses the same channel 0 for DMAE operations for some of the PFs
(e.g., PF0 on Port0). This could lead to concurrent access to the DMAE
channel by FW and driver which is not legal. Hence need to assign unique
DMAE id for FW.
Currently following DMAE channels are used by the clients,
  MFW - OCBB/OCSD functionality uses DMAE channel 14/15
  Driver 0-3 and 8-11 (for PF dmae operations)
         4 and 12 (for stats requests)
Assigning unique dmae_id '13' to the FW.

Changes from previous version:
------------------------------
v2: Incorporated the review comments.

Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>