Convert CONFIG_SF_DEFAULT_* to Kconfig

This converts the following to Kconfig:
  CONFIG_SF_DEFAULT_BUS
  CONFIG_SF_DEFAULT_CS
  CONFIG_SF_DEFAULT_MODE
  CONFIG_SF_DEFAULT_SPEED

I use moveconfig script and then manual check on generated u-boot.cfg
to solve the remaining issue.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
diff --git a/configs/ls1012aqds_tfa_SECURE_BOOT_defconfig b/configs/ls1012aqds_tfa_SECURE_BOOT_defconfig
index 7d0d690..747fa3d 100644
--- a/configs/ls1012aqds_tfa_SECURE_BOOT_defconfig
+++ b/configs/ls1012aqds_tfa_SECURE_BOOT_defconfig
@@ -40,6 +40,9 @@
 CONFIG_FSL_ESDHC=y
 CONFIG_DM_SPI_FLASH=y
 CONFIG_SPI_FLASH=y
+CONFIG_SF_DEFAULT_BUS=1
+CONFIG_SF_DEFAULT_MODE=0
+CONFIG_SF_DEFAULT_SPEED=10000000
 # CONFIG_SPI_FLASH_USE_4K_SECTORS is not set
 CONFIG_FSL_PFE=y
 CONFIG_DM_ETH=y