spi: Rename SPI_SUPPORT to SPI

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

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/imx28_xea_defconfig b/configs/imx28_xea_defconfig
index 985f3c8..f4e65ff 100644
--- a/configs/imx28_xea_defconfig
+++ b/configs/imx28_xea_defconfig
@@ -19,7 +19,7 @@
 CONFIG_SPL=y
 CONFIG_ENV_OFFSET_REDUND=0x90000
 CONFIG_SPL_SPI_FLASH_SUPPORT=y
-CONFIG_SPL_SPI_SUPPORT=y
+CONFIG_SPL_SPI=y
 CONFIG_SPL_PAYLOAD="u-boot.img"
 CONFIG_SYS_LOAD_ADDR=0x42000000
 CONFIG_FIT=y