dts: g12a: add s905d2_u200 and s905y2_u221
PD#156734: add s905d2_u200 and s905y2_u221 for g12a
1. rename g12a_skt.dts to g12a_s905d2_u200.dts
2. cp g12a_dts.dts to g12a_s905d2_skt.dts, and change caps and
f_max for sd_emmc_a
3. cp g12a_skt_buidroot.dts to g12a_s905d2_skt_buildroot.dts, and
change caps and f_max for sd_emmc_a
4. cp g12a_skt.dts to g12a_s905y2_u221.dts, disable ethmac
5. cp g12a_skt.dts to g12a_s905y2_u211.dts
6. set f_max for sd_emmc_c to
50000000
Change-Id: Iffbeffc6dd730cff1c5ac371e237edcc8354b042
Signed-off-by: jianxin.pan <jianxin.pan@amlogic.com>