feat(plat/rcar): change process for Suspend To RAM

- Added the function rcar_pwr_domain_pwr_down_wfi() for power down process.
  And change the sequence to power down.
- Removed clearing the count of psci_locks (PSCI exclusive lock) during
  Warm Boot.

Signed-off-by: Koichi Yamaguchi <koichi.yamaguchi.zb@hitachi.com>
Signed-off-by: Toshiyuki Ogasahara <toshiyuki.ogasahara.bo@hitachi.com>
Signed-off-by: Yoshifumi Hosoya <yoshifumi.hosoya.wj@renesas.com>
Change-Id: I684d54a798a6dccde15fbebe16c6e104cbb470ed
1 file changed