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/deneb_defconfig b/configs/deneb_defconfig
index 5318d7d..13c3587 100644
--- a/configs/deneb_defconfig
+++ b/configs/deneb_defconfig
@@ -32,7 +32,7 @@
 CONFIG_SPL_BOARD_INIT=y
 CONFIG_SPL_SYS_MALLOC_SIMPLE=y
 CONFIG_SPL_SEPARATE_BSS=y
-CONFIG_SPL_POWER_SUPPORT=y
+CONFIG_SPL_POWER=y
 CONFIG_SPL_POWER_DOMAIN=y
 CONFIG_SPL_WATCHDOG_SUPPORT=y
 CONFIG_HUSH_PARSER=y