RDMA/bnxt_re: Add support to handle DCB_CONFIG_CHANGE event

QP1 context in HW needs to be updated when there is a
change in the default DSCP values used for RoCE traffic.
Handle the event from FW and modify the dscp value used
by QP1.

Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://patch.msgid.link/20250107024553.2926983-5-kalesh-anakkur.purayil@broadcom.com


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