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/gwventana_nand_defconfig b/configs/gwventana_nand_defconfig
index 8e84fd7..baeef2b 100644
--- a/configs/gwventana_nand_defconfig
+++ b/configs/gwventana_nand_defconfig
@@ -38,7 +38,7 @@
 CONFIG_SPL_STACK_R=y
 CONFIG_SPL_FIT_IMAGE_TINY=y
 CONFIG_SPL_DMA=y
-CONFIG_SPL_I2C_SUPPORT=y
+CONFIG_SPL_I2C=y
 CONFIG_SPL_NAND_SUPPORT=y
 CONFIG_SPL_OS_BOOT=y
 CONFIG_SPL_POWER=y