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/ls1021atwr_sdcard_qspi_defconfig b/configs/ls1021atwr_sdcard_qspi_defconfig
index 876a92c..2b4ebd9 100644
--- a/configs/ls1021atwr_sdcard_qspi_defconfig
+++ b/configs/ls1021atwr_sdcard_qspi_defconfig
@@ -7,6 +7,8 @@
 CONFIG_OF_CONTROL=y
 CONFIG_DM=y
 CONFIG_SPI_FLASH=y
+CONFIG_SPI_FLASH_ATMEL=y
+CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_NETDEVICES=y
 CONFIG_E1000=y
 CONFIG_SYS_NS16550=y