net: stmmac: setup higher frequency clk support for EHL & TGL

EHL DW EQOS is running on a 200MHz clock. Setting up stmmac-clk,
ptp clock and ptp_max_adj to 200MHz.

Signed-off-by: Voon Weifeng <weifeng.voon@intel.com>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>