Rename SPL_POWER_SUPPORT to SPL_POWER

Rename this option so that CONFIG_IS_ENABLED can be used with it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
diff --git a/configs/chiliboard_defconfig b/configs/chiliboard_defconfig
index 3ab76d5..71b2db7 100644
--- a/configs/chiliboard_defconfig
+++ b/configs/chiliboard_defconfig
@@ -25,7 +25,7 @@
 CONFIG_SPL_NAND_DRIVERS=y
 CONFIG_SPL_NAND_ECC=y
 CONFIG_SPL_NAND_BASE=y
-CONFIG_SPL_POWER_SUPPORT=y
+CONFIG_SPL_POWER=y
 CONFIG_SPL_WATCHDOG_SUPPORT=y
 CONFIG_CMD_ASKENV=y
 # CONFIG_CMD_FLASH is not set