bnxt_en: Optimize recovery path ULP locking in the driver

In the error recovery path (AER, firmware recovery, etc), the
driver notifies the RoCE driver via ULP_STOP before the reset
and via ULP_START after the reset, all under RTNL_LOCK.  The
RoCE driver can take a long time if there are a lot of QPs to
destroy, so it is not ideal to hold the global RTNL lock.

Rely on the new en_dev_lock mutex instead for ULP_STOP and
ULP_START.  For the most part, we move the ULP_STOP call before
we take the RTNL lock and move the ULP_START after RTNL unlock.
Note that SRIOV re-enablement must be done after ULP_START
or RoCE on the VFs will not resume properly after reset.

The one scenario in bnxt_hwrm_if_change() where the RTNL lock
is already taken in the .ndo_open() context requires the ULP
restart to be deferred to the bnxt_sp_task() workqueue.

Reviewed-by: Selvin Thyparampil Xavier <selvin.xavier@broadcom.com>
Reviewed-by: Vikas Gupta <vikas.gupta@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240501003056.100607-6-michael.chan@broadcom.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>