power: rk808: rename to rk8xx

Since this driver can be used for rk8xx series pmic,
let's rename rk808 to rk8xx, to make it clear.

Configs parts are done by sed -i "s/RK808/RK8XX/g" `grep RK808 -lr ./`

Signed-off-by: Jacob Chen <jacob-chen@iotwrt.com>
diff --git a/configs/firefly-rk3399_defconfig b/configs/firefly-rk3399_defconfig
index fcd33ae..f30f131 100644
--- a/configs/firefly-rk3399_defconfig
+++ b/configs/firefly-rk3399_defconfig
@@ -41,10 +41,10 @@
 CONFIG_SPL_PINCTRL=y
 CONFIG_ROCKCHIP_RK3399_PINCTRL=y
 CONFIG_DM_PMIC=y
-CONFIG_PMIC_RK808=y
+CONFIG_PMIC_RK8XX=y
 CONFIG_REGULATOR_PWM=y
 CONFIG_DM_REGULATOR_FIXED=y
-CONFIG_REGULATOR_RK808=y
+CONFIG_REGULATOR_RK8XX=y
 CONFIG_PWM_ROCKCHIP=y
 CONFIG_RAM=y
 CONFIG_SPL_RAM=y