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/P2020RDB-PC_SPIFLASH_defconfig b/configs/P2020RDB-PC_SPIFLASH_defconfig
index 4be0a84..22e9f97 100644
--- a/configs/P2020RDB-PC_SPIFLASH_defconfig
+++ b/configs/P2020RDB-PC_SPIFLASH_defconfig
@@ -11,7 +11,7 @@
 CONFIG_SPL_SERIAL=y
 CONFIG_SPL=y
 CONFIG_SPL_SPI_FLASH_SUPPORT=y
-CONFIG_SPL_SPI_SUPPORT=y
+CONFIG_SPL_SPI=y
 CONFIG_MPC85xx=y
 # CONFIG_CMD_ERRATA is not set
 CONFIG_TARGET_P2020RDB=y