i2c, zynq: convert zynq i2c driver to new multibus/multiadapter framework

- add zync i2c driver to new multibus/multiadpater support
- adapted all config files, which uses this driver

Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Michal Simek <michal.simek@xilinx.com>
diff --git a/README b/README
index 53e56bb..c97ff0a 100644
--- a/README
+++ b/README
@@ -2071,6 +2071,11 @@
 		  - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
 		  - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
 
+		- drivers/i2c/zynq_i2c.c
+		  - activate this driver with CONFIG_SYS_I2C_ZYNQ
+		  - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
+		  - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
+
 		additional defines:
 
 		CONFIG_SYS_NUM_I2C_BUSES