net/bnxt: fix check for PTP support in FW

net/bnxt: fix check for PTP support in FW

On Thor, driver must use HWRM to access the timestamp information.
Driver should not advertise PTP support to application
if PTP information is not available via HWRM commands.

Fixes: 6cbd89f9f3d8 ("net/bnxt: support PTP for Thor")
Cc: stable@dpdk.org
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>