RDMA/bnxt_re: Update the correct DB FIFO depth and mask for GenP7

GenP5 and P7 devices have different DB FIFO depth. Use different
values based on the chip context.

Instead of hardcoding doorbell FIFO related values, get it
from the HWRM interface. Maintain backward compatibility
by having default values when FW is not providing the doorbell
FIFO related values.

Signed-off-by: Chandramohan Akula <chandramohan.akula@broadcom.com>
Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1719456065-27394-2-git-send-email-selvin.xavier@broadcom.com


Signed-off-by: Leon Romanovsky <leon@kernel.org>