Convert CONFIG_SYS_I2C_MXC et al to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_I2C_MXC
   CONFIG_SYS_I2C_MXC_I2C1
   CONFIG_SYS_I2C_MXC_I2C2
   CONFIG_SYS_I2C_MXC_I2C3
   CONFIG_SYS_I2C_MXC_I2C4

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/imx8mq_evk_defconfig b/configs/imx8mq_evk_defconfig
index b778c17..ac1e781 100644
--- a/configs/imx8mq_evk_defconfig
+++ b/configs/imx8mq_evk_defconfig
@@ -3,6 +3,9 @@
 CONFIG_SYS_TEXT_BASE=0x40200000
 CONFIG_ENV_SIZE=0x1000
 CONFIG_ENV_OFFSET=0x400000
+CONFIG_SYS_I2C_MXC_I2C1=y
+CONFIG_SYS_I2C_MXC_I2C2=y
+CONFIG_SYS_I2C_MXC_I2C3=y
 CONFIG_DM_GPIO=y
 CONFIG_DEFAULT_DEVICE_TREE="imx8mq-evk"
 CONFIG_SPL_TEXT_BASE=0x7E1000
@@ -39,7 +42,6 @@
 CONFIG_SAVED_DRAM_TIMING_BASE=0x40000000
 CONFIG_DM_I2C=y
 CONFIG_SPL_SYS_I2C_LEGACY=y
-CONFIG_SYS_I2C_MXC=y
 CONFIG_SUPPORT_EMMC_BOOT=y
 CONFIG_FSL_USDHC=y
 CONFIG_PHYLIB=y