sf: Move SPI flash drivers to defconfig

There are already Kconfig options for SPI flash drivers, but we
have not moved them from config.h to defconfig files. This commit
does this in a batch.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/configs/sh7753evb_defconfig b/configs/sh7753evb_defconfig
index 7bac054..9992cff 100644
--- a/configs/sh7753evb_defconfig
+++ b/configs/sh7753evb_defconfig
@@ -17,4 +17,6 @@
 # CONFIG_CMD_SETEXPR is not set
 # CONFIG_CMD_MISC is not set
 CONFIG_SPI_FLASH=y
+CONFIG_SPI_FLASH_MACRONIX=y
+CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_USE_PRIVATE_LIBGCC=y