octeontx2-pf: fix hardware timestamp issue for ptp slave

commit 2ca3d615dc07f7b8e2bc584c1ec57fff4ea2fb06 from
git@git.assembla.com:cavium/WindRiver.linux.git

In a scenario where initially driver is configured as One-step  PTP
master and later reconfigured as ptp slave, hardware timestamping is
not working. This patch fixes the same.

Fixes: fac93affe62d ("octeontx2-pf: Add support for ptp 1-step using
timecounter")

Change-Id: Ia27546be9968799cc34b51a1bb591b6046818163
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/86504


Reviewed-by: Naveen Mamindlapalli <naveenm@marvell.com>
Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>