i.MX6DL: mamoj: Add I2C support

i.MX6DL Mamoj has i2c3 and i2c4 buses, add support
through DM_I2C with dt definition.

i2c log:
Reviewed-by: Stefano Babic <sbabic@denx.de>

=======
=> i2c bus
Bus 2:  i2c@021a8000
Bus 3:  i2c@021f8000
=> i2c dev 2
Setting bus to 2
=> i2c speed 400000
Setting bus speed to 400000 Hz
=> i2c probe
Valid chip addresses: 20 51 53
=> i2c md 53 0xff
00ff: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
=> i2c md 51 0xff
00ff: a8 08 40 50 09 43 46 52 42 18 80 8e ae a9 d0 53    ..@P.CFRB......S
=> i2c dev 3
Setting bus to 3
=> i2c speed 100000
Setting bus speed to 100000 Hz
=> i2c probe
Valid chip addresses: 08 40 48 4B
=> i2c md 08 0xff
00ff: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ................

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Simone CIANNI <simone.cianni@bticino.it>
Signed-off-by: Raffaele RECALCATI <raffaele.recalcati@bticino.it>
diff --git a/arch/arm/mach-imx/mx6/Kconfig b/arch/arm/mach-imx/mx6/Kconfig
index 8f469c4..b09e8f1 100644
--- a/arch/arm/mach-imx/mx6/Kconfig
+++ b/arch/arm/mach-imx/mx6/Kconfig
@@ -228,6 +228,7 @@
 	select DM
 	select DM_ETH
 	select DM_GPIO
+	select DM_I2C
 	select DM_MMC
 	select DM_THERMAL
 	select SPL