net: ravb: Fix lack of register setting after system resumed for Gen3

[ Upstream commit c2b6cdee ]

After system entered Suspend to RAM, registers setting of this
hardware is reset because the SoC will be turned off. On R-Car Gen3
(info->ccc_gac), ravb_ptp_init() is called in ravb_probe() only. So,
after system resumed, it lacks of the initial settings for ptp. So,
add ravb_ptp_{init,stop}() into ravb_{resume,suspend}().

Fixes: f5d7837f ("ravb: ptp: Add CONFIG mode support")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>