dm: i2c: Add driver for Cadence I2C IP

This is a possible drop in replacement for drivers/i2c/zynq-i2c.c

Since this is cadence IP it has been renamed to cdns-i2c,
to make sense with the compatible string.

Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index c75c579..167424d 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -16,6 +16,7 @@
 obj-$(CONFIG_TSI108_I2C) += tsi108_i2c.o
 obj-$(CONFIG_SH_SH7734_I2C) += sh_sh7734_i2c.o
 obj-$(CONFIG_SYS_I2C) += i2c_core.o
+obj-$(CONFIG_SYS_I2C_CADENCE) += i2c-cdns.o
 obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o
 obj-$(CONFIG_SYS_I2C_DW) += designware_i2c.o
 obj-$(CONFIG_SYS_I2C_FSL) += fsl_i2c.o