Add capability to specify warning notification period to help firmware
adjust to congestion accordingly.

Link: https://lore.kernel.org/r/20220819011736.14141-5-jsmart2021@gmail.comCo-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>