exynos5: fix build break by adding CONFIG_POWER

Move the configs listed below from exynos5-dt-common.h to exynos5-common.h:
- CONFIG_POWER
- CONFIG_POWER_I2C
fixes build break for Arndale and Smdk5250 boards.

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>

include/configs/exynos5-common.h

@@ -149,6 +149,10 @@
 #define CONFIG_OF_SPI
 #endif
 
+/* Power */
+#define CONFIG_POWER
+#define CONFIG_POWER_I2C
+
 #ifdef CONFIG_ENV_IS_IN_SPI_FLASH
 #define CONFIG_ENV_SPI_MODE	SPI_MODE_0
 #define CONFIG_ENV_SECT_SIZE	CONFIG_ENV_SIZE