Convert CONFIG_I2C_SET_DEFAULT_BUS_NUM et al to Kconfig

This converts the following to Kconfig:
   CONFIG_I2C_SET_DEFAULT_BUS_NUM
   CONFIG_I2C_DEFAULT_BUS_NUMBER

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/ls1043ardb_nand_defconfig b/configs/ls1043ardb_nand_defconfig
index 783efe0..fcfe074 100644
--- a/configs/ls1043ardb_nand_defconfig
+++ b/configs/ls1043ardb_nand_defconfig
@@ -57,6 +57,7 @@
 CONFIG_FSL_CAAM=y
 CONFIG_DM_I2C=y
 CONFIG_SPL_SYS_I2C_LEGACY=y
+CONFIG_I2C_SET_DEFAULT_BUS_NUM=y
 CONFIG_SYS_I2C_EEPROM_ADDR=0x53
 CONFIG_FSL_ESDHC=y
 CONFIG_MTD=y