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/ls1012a2g5rdb_tfa_defconfig b/configs/ls1012a2g5rdb_tfa_defconfig
index 7360a13..81e31cd 100644
--- a/configs/ls1012a2g5rdb_tfa_defconfig
+++ b/configs/ls1012a2g5rdb_tfa_defconfig
@@ -41,6 +41,7 @@
 CONFIG_DM=y
 CONFIG_SATA_CEVA=y
 CONFIG_DM_I2C=y
+CONFIG_I2C_SET_DEFAULT_BUS_NUM=y
 CONFIG_FSL_ESDHC=y
 CONFIG_MTD=y
 CONFIG_DM_SPI_FLASH=y