forked from Mirrors/opensbi

The Kendryte K210 UARTHS is compatible with SiFive UART. So use the sifive uart driver and remove the k210 uarths platform code. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>