RDMA/mana_ib: Fix DSCP value in modify QP

Convert the traffic_class in GRH to a DSCP value as required by the HW.

Fixes: e095405b ("RDMA/mana_ib: Modify QP state")
Signed-off-by: Shiraz Saleem <shirazsaleem@microsoft.com>
Signed-off-by: Konstantin Taranov <kotaranov@microsoft.com>
Link: https://patch.msgid.link/1752143085-4169-1-git-send-email-kotaranov@linux.microsoft.com


Reviewed-by: Long Li <longli@microsoft.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>