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/theadorable_debug_defconfig b/configs/theadorable_debug_defconfig
index a298e41..0104324 100644
--- a/configs/theadorable_debug_defconfig
+++ b/configs/theadorable_debug_defconfig
@@ -27,7 +27,7 @@
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_DISPLAY_BOARDINFO_LATE=y
-CONFIG_SPL_I2C_SUPPORT=y
+CONFIG_SPL_I2C=y
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_BOOTZ=y
 CONFIG_CMD_GPIO=y