bnxt_en: Initiallize bp->ptp_lock first before using it

bnxt_ptp_init() calls bnxt_ptp_init_rtc() which will acquire the ptp_lock
spinlock.  The spinlock is not initialized until later.  Move the
bnxt_ptp_init_rtc() call after the spinlock is initialized.

Fixes: 24ac1ecd ("bnxt_en: Add driver support to use Real Time Counter for PTP")
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Reviewed-by: Saravanan Vajravel <saravanan.vajravel@broadcom.com>
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Damodharam Ammepalli <damodharam.ammepalli@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>