octeontx2-bphy-netdev: cnf95n: ptp: use 950MHz clock for ptp slave

commit 94c472848ef3acf1b906d469382b12a65e147f2e from
git@git.assembla.com:cavium/WindRiver.linux.git

Use 950MHz clock input for CN95xxN PTP slave operation.

Change-Id: I1fbb483578e99b73686760455a4c44db4ab85280
Signed-off-by: Naveen Mamindlapalli <naveenm@marvell.com>
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/79996
Reviewed-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Tested-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>