i2c: Rename SPL/TPL_I2C_SUPPORT to I2C

Rename these options so that CONFIG_IS_ENABLED can be used with them.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
diff --git a/configs/Empire_electronix_d709_defconfig b/configs/Empire_electronix_d709_defconfig
index eb6a316..3811808 100644
--- a/configs/Empire_electronix_d709_defconfig
+++ b/configs/Empire_electronix_d709_defconfig
@@ -16,6 +16,6 @@
 CONFIG_VIDEO_LCD_BL_EN="AXP0-1"
 CONFIG_VIDEO_LCD_BL_PWM="PB2"
 # CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
-CONFIG_SPL_I2C_SUPPORT=y
+CONFIG_SPL_I2C=y
 CONFIG_CONS_INDEX=2
 CONFIG_USB_MUSB_HOST=y