octeontx2-af: Move validation of ptp pointer before its usage

octeontx2-af: Move validation of ptp pointer before its usage

[ Upstream commit 7709fbd4922c197efabda03660d93e48a3e80323 ]

Moved PTP pointer validation before its use to avoid smatch warning.
Also used kzalloc/kfree instead of devm_kzalloc/devm_kfree.

Fixes: 2ef4e45d99b1 ("octeontx2-af: Add PTP PPS Errata workaround on CN10K silicon")
Signed-off-by: Naveen Mamindlapalli <naveenm@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: Sai Krishna <saikrishnag@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>