bnxt_en: Add ETH_RESET_AP support

Add ETH_RESET_AP support handling to reset the internal
Application Processor(s) of the SmartNIC card.

Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Acked-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>