zynq-common: Define CONFIG_SYS_I2C_ZYNQ based on board config

Enable CONFIG_SYS_I2C_ZYNQ only if it has either I2C0 or I2C1
enabled in a board config.This fixes the issue of i2c error
during board init if board specific doesnt have either I2C0
or I2C1.

Signed-off-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

include/configs/zynq-common.h

@@ -179,7 +179,10 @@
 # define CONFIG_CMD_FS_GENERIC
 #endif
 
+#if defined(CONFIG_ZYNQ_I2C0) || defined(CONFIG_ZYNQ_I2C1)
 #define CONFIG_SYS_I2C_ZYNQ
+#endif
+
 /* I2C */
 #if defined(CONFIG_SYS_I2C_ZYNQ)
 # define CONFIG_CMD_I2C